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Destroyed by Aftermarket Scantool ?! (Car Ran Perfect Before this)
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- Published on Mar 6, 2026
- This vehicle ran perfectly until the owner connected an aftermarket scan tool.
Right after that moment, the car would never run again.
No matter what the owner tried the problem wouldn’t go away. Even a specialist was unable to fix it. What started with connecting an aftermarket scan tool turned into a complete no-start mystery.
In this video, we dive deep into real-world automotive diagnostics to uncover what actually went wrong.
#diagnosticcase #shoplife #realworlddiagnostics #problemsolving #mechanic #repair
You’ll see:
✔️ Step-by-step troubleshooting of a no-start condition
✔️ The importance of asking the customer the right questions
✔️ Programming of engine ECU
✔️ Whether the aftermarket diagnostic tool really damaged the vehicle
Modern cars rely on complex electronics and computer systems and sometimes a single event can trigger a cascade of problems.
Was the scan tool really the cause… or just a coincidence?
Watch until the end to find out.
👍 Like • 💬 Comment • 🔔 Subscribe for more real diagnostic cases
Enjoy the video!
Check out my Second channel;
/ @ddtsb
Check out my website ; www.diagnoseda...
For Diagnosedan Tsb visit : www.diagnoseda....
For the Topdon tool used in the video:
US: www.topdon.us
UK: www.diagnostic...
EU: eu.topdon.com
For business inquiries ( not for technical questions!); Diagnosedan@gmail.com 
Autos & Vehicles
This vehicle ran perfectly until the owner connected an aftermarket scan tool.
Right after that moment, the car would never run again.
No matter what the owner tried the problem wouldn’t go away. Even a specialist was unable to fix it. What started with connecting an aftermarket scan tool turned into a complete no-start mystery.
In this video, we dive deep into real-world automotive diagnostics to uncover what actually went wrong.
#diagnosticcase #shoplife #realworlddiagnostics #problemsolving #mechanic #repair
You’ll see:
✔ Step-by-step troubleshooting of a no-start condition
✔ The importance of asking the customer the right questions
✔ Programming of engine ECU
✔ Whether the aftermarket diagnostic tool really damaged the vehicle
Modern cars rely on complex electronics and computer systems and sometimes a single event can trigger a cascade of problems.
Was the scan tool really the cause… or just a coincidence?
Watch until the end to find out.
👍 Like • 💬 Comment • 🔔 Subscribe for more real diagnostic cases
Enjoy the video!
Check out my Second channel;
/ @ddtsb
Check out my website ; www.diagnosedan.com
For Diagnosedan Tsb visit : www.diagnosedan.com/diagnosed...
For the Topdon tool used in the video:
US: www.topdon.us
UK: www.diagnosticconnections.co.uk/
EU: eu.topdon.com
For business inquiries ( not for technical questions!); Diagnosedan@gmail.com
Dan, do you think using the code clear function would have worked on the tuned software even though it reported no codes? Interesting.
Why didn't check your fuses first,Dan?
Danny, ik ging echt helemaal stuk bij het gedeelte waar je tachometer probeerde te zeggen 😂😂😂.. tach meter, rpm gauge is ook allemaal goed trouwens 👍🏼 Geweldige content, ik geniet er als (ex) monteur echt van.
I like your simplistic presentation.
There's just one thing.
If it's called a Run-no, why would you expect it to run?
His scan tool used prior to having brought it to you, may be diabolically designed with a warped mind.
Ask me how I know.
Hi Dan
I was wondering, in the Topdon Phoenix Max, you also have the ability to update and change software, couldn't that work for this car? 🤔
I think, most likely a throttle body adaptation was performed while testing the new diagnostic tool. Unfortunately, in a Megane 3 2.0TCe with an EMS3110 ECU, the car sometimes refuses to start after this procedure, just like in the example in the video. I know this because I have the exact same car and follow facebook groups related to it. From time to time, posts appear asking for help because the car refuses to start after performing the throttle body adaptation procedure. I even reverse-engineered the engine control unit software and found a function that handles throttle body learning, but my car does not want to break down the same way like the one in the video, leaving me unsure which variables in the function code have incorrect values, so I can't tell what is the exact cause of this problem. Generally speaking, the throttle body adaptation fails, and the failure prevents the injectors from opening.
I can say this isn't the fault of an aftermarket diagnostic tool, as I've also seen this happen using CLIP. It's almost certainly not the fault of engine software modifications, as engine tuning relies solely on modifications to the software calibration section, not the software code (unless someone accidentally changed the throttle body learning scenario, but this is very unlikely).
I'm glad that restoring the stock software helped, but the problem can still occur when using the throttle body adaptation function. However, this can be easily fixed by overriding the "End of the first learning phase, after first key on" variable in DDT4ALL/Renolink or by sending 2E250101 to the engine control unit.
This is good info to know fella and a real potential booby trap for a lot of techs.
When you over ride the 1st stage do you just turn off the ign or force it on the tool?
I have zero use for this but someone will find this extremely useful, so nice one for posting a decent amount of info ❤
Been there myself with it. No matter what learning I tried, I couldn't get it to start so I diagnosed it as a bad ecu. A quick flash in tuners and it was running again. Customer said they cu was replaced but I doubt that
I think some remapping techs will use certain shortcuts in the tuning process which can negatively affect the ECMs ability to use certain failsafe functions it was normally programmed for. There are many ways to scale certain fueling / timing tables and sensor parameters and avoid setting DTCs through disabling some monitors. Forcing the ECM to ignore things like overboost can disable some diagnostic functions that would reveal causes of operating the engine out of set parameters. This can create conflicts in the software which are normally designed to allow a compromised mode of vehicle operation when something in the engine management fails ie. a no start condition without any injector pulses. This is why its bad that some tuners will just turn off some monitors, which is much worse than just changing the fault detection parameters where the ECM will set DTCs.
But if the software wasn't altered the ECU would still throw fault codes. The fact that all fault codes were ignored ("coded out") was already a telltale sign that someone also messed with the ECU software, not just the motor map.
My left ear is enjoying the video
Yeah. Painfully so.
jeeeesus i was troubleshooting my speakers, thank you
Sure nuff!
My right ear isn't feeling the love.
I thought my headphones were kaputt, again
Customer comment, "There's nothing wrong with it, it just won't run" Lol
😂 heard that one many times
Small issue. Then why did You towed it to me.
it was fine last time it started
Sounds like a classic line! 😂
My first thought was "out of gas"😂
It sort of was, given that the injectors weren't being fired.😉 I was trying to look for the fuel gauge as he tried starting it, too.
"Ain't got no gas innit,.. mmmmhuh." Carl
Lol. Cheers
The dreaded E fault
Thankfully not a fuel issue this time! 😂
my was diesel instead of petrol
I wonder if clearing the non-existent DTCs would have enabled the car to start🤔
I was wondering that
We would need source code of ecu if software runs something special internal reset when reseting spesific codes then it would not work because they were not set
Likely not, cause there aren't any, hence I'd assume tool won't even send clear signal.
@jothainbut the fault codes had to be there or it would have started, I guess it depends on how the software was written.
@samueljames9342 That was my point. If scan tool doesn't acknowledge errors, it might simply not send clear code at all. Impossible to say unless code is seen from the reader.
When the injector was not working, I immediately knew remapped and bricked.
Gosh your patience deserves double payment.
I'm pretty sure he get payed fairly, when they finally get to him (as a last resort) and have tried "everything" but him. If the cost is less than a new car it's worth it.
I have this stuff on a weekly base
The ecu editing industry are everywhere this day
You can buy remap service as low as 10euro this days
But this is what you get
Remaps are good as long as your engine don’t have issues
Haha, it definitely takes a lot of patience sometimes!
@Diagnosedan But it's people like you that keep the evolution going. It's just a bonus that you are willing to share with us all the hours of your head scratching.
I'm french and i loved your 'hum' and remarks about french engineers 😂
they just seem to want to design things from a clean sheet
I love France and the French, but your engineers are certainly unique!
@elcheapo5302😂😂😂😂
The French copy no one and NOBODY copy's the French.
@emgriffiths9743seem not want 😂
Nice one Dan! In hindsight the car model and colour should have made you suspect that it might be a tuned car. 🏎
Thanks for the insight! You're right, that could have been a clue. 😂
It's amazing when I follow with you all diag steps, each time we learn something new...👍
That's great to hear! Thanks for watching. 😊
This is like listening to Ivan from Pine hollow diagnostics -- with a different accent 😂
No way Ivan does not break down the system as clearly as Dan does. The things I like about Dan videos, besides the clear thought process, is he sets up tripods so it shows clearly what he’s doing at during the video. I can’t tell what’s going on in Ivan’s videos because he tries to hold a camera in his hand. Dan is a man.
Ivan and Dan are two different techs. Each to their own.
I was hoping to see the Bloopers on you saying "Tachometer!"
"Rev counter!" Problem solved? LOL😅
🌮🌮🌮🌮🌮🌮🌮
😂😂
The fact that the presence of a fault code can disable a vehicle is just crazy
It makes sense if an adaptation procedure isn't completed and that's why there's a DTC to stop injectors because it might try to idle at 7000rpm.
It wouldn't come across that failure mode in any kind of normal DTC operation that way, only in a technician's garage
Some fault codes need to disable the vehicle because running with that fault would be dangerous. For example if the crankshaft position sensor is not working properly the ecu cannot time the ignition and the injection correctly. Same with camshaft position sensor in cars with VVT like this one.
@MrAlex3461 99% cars not do this. why it makes sense for only this car?
@ky7299 but why not just let it start buy only go low speed. so it can go to safe zone.
@jianbinchen2881Because the engine simply cannot run without a crankshaft position sensor. It doesn't know when to fire the spark plugs so it cannot ignite the fuel at the correct time. If it ignites it early while the intake valves are still open the flame front will go up through the intake manifold and possibly start a fire in the engine bay. If it ignites it too late then the flame front may hit the pistons when they are going up and destroy them or it may escape through the exhaust valves, melt the exhaust and start a fire.
Excellent video Danny, I appreciate your methodical approach in figuring out what was going on. Well done mate 💪💪👏👏
Thanks so much for the kind words! Really appreciate it! 👍
Doctor Dan did it again. brilliant work Dan, great watching. cheers NZ
Thanks for the kind words, much appreciated! 😊
oh boy a new Diagnose Dan video! makes it a great Tuesday.
Thanks for watching! Hope you enjoyed this one. 👍
Dan you are ABSOLUTELY one of the best on RUclips. Just amazing videos and always with humor and information galore! The engineer / Croissant thing was DANG GOOD!
I really appreciate you saying that! It means a lot to hear you enjoy the videos. 👍
Concordo pienamente. Quando toccano le cose e non te lo dicono, diventa quasi impossibile trovare un guasto. Quando, più, ci si mette di mezzo l',elettronica e l'informatica, basta cambiare un parametro che si causano dei danni
Couldn't agree more, it makes troubleshooting incredibly difficult! 👍
So satisfying to watch. You just know Dan allways find the fault
😁
I absolutely love your videos. On top of being very instructive they're very enjoyable and entertaining to watch as well, filming and narration are very good :)
Thank you so much for the kind words! Really appreciate it! 😊
Great investigation very enlightening about aftermarket tuning
Glad you found it insightful! 👍
Thank you Professor Dan for running us through all the basic checks which sometimes we forget costing us loads of time diagnosing, Great Video
You're very welcome! I'm glad it was helpful. 👍
Seat reclined, check! no one about, check! ready to be educated, check! absolutely brilliant diagnosis Dan and once again highlighting the importance of having all the information about the vehicle you’re working on, ps Dan if you’re struggling to remember a certain word in English don’t worry about it just say it in Dutch and I’ll go to google translate and find out the component you’re describing, another brilliant post, enjoy the next weekend off with your family
Thanks for the awesome feedback and the tip about my English! 😂 Enjoy your weekend too!
Thanks for the awesome feedback and the tip about my English! 😂 Enjoy your weekend too!
A good tunner does not remove DTC code, they just give a bigger margin for the new values.
I would NEVER remove all codes like that.
Thanks for sharing your insight on DTC codes and tuning!
Foarte instructivă experiența și mai ales distractivă, îmi place optimismul lui Cezar să tot mergi cu el la aventuri din astea 😂😂😂
Mulțumesc! Mă bucur că te-ai distrat cu aventurile noastre. 😂👍
Liking the subtle digs at Renault. I can imagine most of us viewers that have experience with working on French stuff used more direct expletives!
I run a 2008 Grand Scenic as a daily driver and a 2005 Grand Scenic as a backup car. I'm a hobby mechanic, so I love the fact that they're always breaking, so I'm always learning something new, and always have something to do to them.
The daily driver actually broke today, so I'm using the backup car, and this weekend I get to replace the driveshafts! Yay!
@Zeem4The early 2000s Renaults are pretty simple. Of course they do have their quirks like melting/loosening rear light connectors leading to them not working... And then you go to check the fuses and find out they are in the engine bay, upside down covered by plastic, the removal of which requires removing the battery, its tray, the ecu etc... 😂
Haha, I try to keep it family-friendly on here! 😂
Excellent diagnosis Dan! You fixed it once again! Looks like you will be having a lot of fun with your new programming tool.😜 Hope all is well with you and your family.
Glad I could fix it! And thank you Glen, all is well here. Hope you're doing great too! 👍
This is really a difficult case. Great job Dan 😍
I appreciate that! It was definitely a tricky one. 👍
We recently bought a 2020 Audi A6 Quattro and can across your channel, great to see how you approach these issue with no jumping to conclusions.
I'm pretty sure I need your videos as reference one day with my A6. Thanks for the great contend.
Cool mystery. Thanks, Dan!
Glad you enjoyed it! 👍
I really enjoyed your video. First time, watcher with plans to watch more. Very professional and great explanations.
Welcome to the channel! Thanks for the awesome feedback, it means a lot! 👍
Interesting case Dan! Thanks for teaching us and taking us along.
You're very welcome! Glad you enjoyed it. 👍
Absolutely awesome video, I wouldn't like to have to pay for this information, as it would be very costly.
Keep up the great work Mr
Thanks for the awesome feedback, I really appreciate it!
Fantastic Dan. That’s one lucky customer. He could have spent a fortune and a lot of time trying to fix that!
Glad I could help him out! 😊
That was an awesome problem! Let’s put that one behind the ear. Thank you for an great video! 🙏👏
Glad you found it helpful! Thanks for watching. 👍
Great video Dan. Considering that the software was modified within the ECU, most likely a standard diagnostic tool introduced a normal command, but the modified software interpreted the command incorrectly and disabled the ECU to not function as expected.
Glad you enjoyed the video and thanks for sharing your thoughts on the issue! 👍
Aside from your skills...the breakthrough came when you recalled that cars with "a tune" often do not trigger fault codes. Good on you for recalling that nugget of knowledge. The new diag. and programming equipment which you were able to use is absolutely going to be the hot ticket when it hits the market. Thanks for bringing us along on this journey.
Dont ask me how i know🤣 i wasted a lot of time on tuned cars throughout my career😂
Just the best diag channel on YT
You've not watched scanner Danner then ?
Thank you!
@paulsimpson2232there are many great techs on YT and Paul is certainly one of them!
@paulsimpson2232 😂
Great video and walkthrough! Looking forward to the next one 🤘👌
Appreciate the support, stay tuned! 🎥
The second you said "bodyman," I knew it was going to be weird!
😂
😂
Dan, you just don't know how much we wait for your videos. Pls take time for your fans and pls post more videos.
I do as much as i can😀
I was screaming at my screen that the Error Codes must have been masked somehow 😂😂😂 this should be a lesson for people mapping their vehicles with strange softwares
Egr Remover tool v2 lol. Ive got this in the past, it drove me crazy till i found it
Did you even try to erase faultcodes even it said there arent any?
What do we want to bet the owner returned to the tuner to put the Stage 2 on it again afterwards though? LOL. Either that or will go to a different tuner/company. Powder be addictive, so going back to stock is gonna be a letdown for the owner.
@mleussin Sometimes, the test tool wont try to clear codes if there are not any.
When I was a transmission specialist with Pontiac in the late 90's. GM installed the LS1 engine in the Trans Am Firebirds. Naturally all the young fellows just HAD to have them tuned. This, in turn bar-b-que'd the automatic transmission. GM had a TSB on the program file numbers flagging as not recognized. A factory reprogram was mandatory when repairs were made.
Prachtige uitleg !
Wat die aftermarket scantool nu precies fout deed is voor mij een raadsel en de oude afstandsbediening zal gewoon stuk zijn.
Het is begrijpelijk dat een autotechnicus hier niet snel of helemaal niet uit komt,.
Fantastisch gedaan Dan.
Fijn om te horen dat de uitleg gewaardeerd wordt! Bedankt voor de complimenten!
Very informative. Amigo. Thank you very much
The way you teach bro is so good.
Glad to hear you find my teaching style helpful! 😊
Recently, Pine Hollow Auto Diagnostics (PHAD), took a long time diagnosing a vehicle that had no fault codes. Turned out that a module for an option on the vehicle was "Greyed-out" on the scan tool. It was a luxury car and the module for the seat warmer wasn't online. 4:20 I noticed some grey boxes and wondered if this was going to be the same problem.
Oh yes it was the climate seat module that failed It was on a Lincoln MKX I believe.
@neilmurphy845
I remember that diag.
Ivan saw the module missing and enabled the module
The customer had installed a heated seat and didn’t tell .
The module was never installed
So Ivan left the seat heater unplugged.
As I’ve said before, customers will not tell you the whole story. Such as the case with this car.
It sounded very odd, it kinda got me a bit concerned because I use my scan tool to fix my family’s vehicles.
@2nickles647Ya It's crazy how they won't tell the full story I think Eric O had a saying that customers say if you say less you pay less
Haven't seen that video yet, i'll take a look!
Great video. Smelling the tail pipe exhaust is a quick way to check if gas is being injected.
Glad you enjoyed the video! Thanks for sharing that insight.
Grappig, ik had dezelfde gedachtegang. Alhoewel ik er bijna van overtuigd van dat de sleutel toch de fout zou geven met een een of ander Franse "nieuwigheid" 😂
Great video Danny
Bedankt voor het kijken en je leuke reactie! 👍
By far my favorite channel on RUclips and i also love the bloopers lol
Morale of the story.
Don't tamper with OEM mapping 😅
A proper tune wouldn't mask all error codes.
😂
Interesting diagnosis, this is one of the reasons I like my cars stock, as from the factory. ☀
I can definitely see the appeal of keeping things stock!
just a tip, u can always "force" a clear fault code via OBD2 generic protocol instead of manufacturer specific diagnostic. this for when u have "ghost faults" hidden by modified sw.
Simply pilling battery for couple of haurs also is great option!
You're a real doctor! I love your teaching style. I wish I could work with you. 🥰
Thanks for the kind words! 😊
That new big ass scantool with live support and access to all OEM stuff sounds like it will cost at least one of your kidneys.
seen normal tools that can uppdate and even use older software its easy to change.. my polo 1.6tdi had a dieselgate upgrade and i change to a older software pre dieselgate. its was not hard.. scantools had a lot of version of software for that ecu.. so first i downgrade software to a pre dieselgaten then tune it and its work nice and still have working fault codes if i unplug stuff =) but it a friend of me that tune that car =) and he still have my stock software. =)
as a good tuner always keeps.
and he can turn fault codes off like egr and dpf if i need. but you never turn of fault codes for injektors and stuff like that its stupid.. i think ecu whent in to a safemode and when it got new software it reset it self. after at systemcheck.. and it fix all problem. but is hard to see now. if you not safe that tune file and try instal it and try all stuff again.
We have a similar one in Italy from CelesteMap. The tool isn't crazy expensive (but not cheap) but having "all tools for all oem vehicles" is MUCH MUCH MUCH more expensive ;)
@davidsten780616 what scantool are you talking about
The Topdon scan tools are quite reasonably priced for professional equipment imo.The high end "Phoenix Max" is 3750 euro and includes a 4 channel oscilloscope. Not the kind of money most DIYers would be willing to spend, but for a bigger shop it would pay back pretty quickly.
I'm not sure about the costs but usually their hardware is not that expensive as selling hardware is not their business model. The business model is that you pay per service if you want them to remotely take over the vehicle and program it for for example. And in my opinion those rates are also very reasonable!
Nice catch, that's good to know that some reprogramers will turn off fault code registration, thanks..!!
Thanks for your comment!
I worked as a field technician for a major kitchen equipment service company. 90% of the time listening to the client's complaint would at the very least, point me in the direction of the problem. And paying attention to the little details of how the equipment operates. 👍🏼✌🏼
Great work as always ,knowledge is a fantastic tool bloopers are great keep em coming
Glad you enjoyed it! 👍
As always, a clever clever guy. Goes to show that even with all these computers, it still comes down to detective work.
just a note on sound if possible to put your mic audio on both channels? currently dialogue is only in the left channel and music is stereo.
Thanks for the feedback on the audio, I'll definitely look into that for future videos!
Again another brilliant lesson in systematic diagnoses.
Thanks for the kind words! 👍
After you fixed the problem, what about the 2 keys problem was that sorted as well.
No
A master class in diagnostic demonstration.
Most tune-up shops don't know or don't care about anything else apart from hp. That is why I also don't like tuned vehicles
I guess they can only do mapping, if they were really good, they could change the limits for setting a faultcode instead of just disabling the fault code storing alltogether.
In any case it would be a b*tch working on a car, that would show no codes.
Absolutely fascinating and a warning shot across the bows of anyone (like me) that was considering messing with something that actually works. Thank you Dan, lesson sustained.
As an American, I just think this car is very cool. eye searing yellow, manual transmission, hatchback. I wish we had options for this in the states without spending Golf R money.
As a European I do also think that your mopar and muscle cars are cool! Big fan of Uncle Tony's Garage, but yes, the hot hatch's just didn't seem to take hold in the US which is a shame!
In Australia we have the best of both worlds. But keep in mind these are comparably priced to Golf Rs in the used market if not slightly cheaper. But keep in mind these hot Renaults are heaps more fun to drive and more comfortable on track than their counterparts. Some of the older 2010ish rs250 models are pretty cheap at around $10k but golfs of that era are only about $12k. You can even pick up some early A45 AMGs for sub $20k AUD over here. Most hatchbacks are very undervalued these days.
They are pretty cool cars!
Hats off to Dan thats top level diagnostic honestly i appreciate u for what u doing and sharing ur experince.
Thank you Dan !
Thanks for the kind words! I appreciate the support. 👍
This is a lesson for people using scan tools while not knowing what they're doing. Good thing Dan fixed it! and it wasn't him working on someone else's car.
There is a chance that the guy removed sensor plugs trying to set a fault code while practicing with the new scan tool. There isn't much you can learn testing out a new tool on a car showing no faults. So he probably did more than he let on and then feigned ignorance as he felt silly breaking his own car.
@davidoff59 i was the guy, and no i did nothing more (wrong) than Danny told us😅. I rather brake my own car than a customers car.
Another brilliant fantastic diagnosing together... just fascinating Dan...thanks for sharing
Glad you enjoyed it! Thanks for watching! 👍
If the car does not start without erasing the fault codes, I have seen that even if the car has remapped soft. and DTC removed soft. you can still erase the the unseen fault codes. Sometimes it works with the Renault module or EOBD module just erase blindly on the screen and it does the job. But you are very right about the fault finding period where you waste a lot of time to verify everything works and its the ecu from the beginning. The history of the car is very important. I suspect they deleted the original keys and tried to start the car then reprogrammed the new keys but the ECU did not show anything to erase thatswhy the car did not start in the first place.
Removing the battery terminal should have erased the fault codes, that’s why he removed the terminal for a few days.
Not necessarily. A lot of Manufacturers store fault codes in NVRAM, so they don't get lost if power is disconnected.
It's always fascinating to watch your diagnostic process even though I no longer work on my own cars. A logical and deductive approach along with experience is worth ££££. 👍
Ahh, I'm vindicated in my statement on my website on not working on tuned cars!
I absolutely agree with you, I always defend this. Greetings from Türkiye
🤝
@mtyl1993 Greeting from England, fellow standard car diagnoser!
@theweekthatis Im not against modifying a vehicles software to increase torque performance Im against doing it to the original ECU Master boss😏thats why companies introduced gateway locks in the first place I request that you fix the STANDART😅 Range Rover oil coolers that keep exploding Your vehicles are constantly being moved on cranes
Excellent moment at 11:36 and then at 13:34, made me chuckle. Videos like these are pure treasure, I could watch Diagnose Dan and Scotty Kilmer whole day, knowledge at its best!
Thank you!
What is the design logic behind not allowing the vehicle to start when fault codes are stored?
Force people to go to the dealer to unload their pockets?
There are so many ignorant people these days who drive with a fault message until the car breaks down.
It wasn't because there was a fault code stored, but *what* fault codes were stored.
When detecting a problem with the injectors the ECU will typically disable the problem injector entirely as a safety measure. If it can't control the fuel then you get none so it doesn't cause unintended acceleration or rev to the moon for example.
If he had only unplugged 1 injector it's likely the engine would have ran OK just with 3 out of 4 cylinders contributing.
Some times a key off then trying again will work, othertimes you need to clear out the codes.
California mod to protect you from yourself.
Its a Renault...no logic involved😉
I work for Ford motor company and I have a few vehicles here and there where the customer is tuned their Mustang GT and it makes it so difficult to diagnose. You were right on the money by figuring out this problem thank you for sharing it with us. God bless!
Dan said he would not work on a tuned vehicle
I would have loved to check with the mapping software manufacturer and see if this was some "tsb" within the maps/software
i can't beleive! like working on a smartphone! 👏
Thanks! Sometimes these repairs feel more like IT work. 👏
About 2 years ago i had a Mercedes Vito in my shop that had no power, and no fault codes.
After checking the vacuum to the turbo etc, i started to scratch my head a bit.
I disconnected some electrical plugs to do some measurings, everything looked fine...
But then i scanned it again, and still NO fault codes.
That made me think logically that someone had tampered with the ECU.
Because when i disconnected a ABS sensor, the dash showed a ABS fault, and my computer read a fault from the ABS sensor i disconnected...
So i called the owner and asked if he had a DPF or an EGR delete done.
His answer "No, its not been tampered! I had no problems before."
I said, ok, so no modifications with software?
He said again "No, its original"
Then my next question was, how original is it? Still the same HP as from factory?
His response: "Oh when i just bought it i went to a chiptuner and asked how many HP he could get out of it. He said he can tune it to about 210HP instead of the original 136HP for a reasonable price. So i said yes please, sounds good."
I went silent on the phone, untill he said "Euh, are you saying its the chiptuning? Its a chip they put somewhere in, so no modifications on the car, right?"
So after that i told him to drive it to the dealer and put original software back on and learn to live with the standard 136HP...
And you know what? That Vito drove perfectly fine on original software.
Something in that chiptune must have gone wrong after a while, the ECU did not know how to react and turned the power off or something...
Sounds too good to be true, from 136HP to 210HP with chip tuning only without any mechanical modifications 😂🤣
@cahyoh.harimurti8554 Typical chiptuners talking to a oblivious customer.
Sometimes i explain to people more isnt better😂
Good info. I was not aware of this issue . Thanks for the great content !
You're very welcome! Thanks for watching. 👍
I'm old, when I get a crank no start like this, I hook up the scan tool and do the usual checks.
Once I see the signs that spark is present, IE tacho reading at crank and RPM displayed in scan tool, I go to something I was taught as an apprentice.
Add some fuel and see if it starts. It used to be by pouring a little gas down the carb, nowadays I use a barbecue bottle, if it starts and runs, you have spark and a mechanically sound engine.
This is a simple and quick test that can be done by anyone, the car can actually be driven down the road like this.
Now we know we are facing a fuel system issue.
On this vehicle this is where things start getting more difficult and we need people like Dan to come to the rescue.
Yeah The Car Wizard, showed how just a short spray of EasyStart/Ether into the air cleaner intake, then see if the car fires-up and runs for a moment, you then know that the fuel, for whatever reason, is not being getting through to the combustion chambers.
I laughed when you said the car can be driven down the road like this as we regularly drive cars into the workshop with a can of engine start but I'm the only one brave enough to sit under the bonnet
@johnmcnair8854 Yeah I guess the BBQ bottle sitting on the passenger floor is hi tech compared to that. 😁
Hey man iam a really good fan of your account.
I was using heatphones to listen and the sound is only on the left side. You might check that in the future videos.
And you helped me a lot to find out how cars work
Really appreciate you watching and the kind words! Thanks for the heads-up on the audio, I'll look into it. Happy to hear I've been helpful! 👍
This was a tough one Dan, but also a very educational one
Definitely a challenging one, thanks for watching!
😂😂😂😂😂😂 I enjoy 'em bloopers 😂😂😂😂😂😂😂😂. Thank you very much sir. God bless you!
Good to hear you enjoyed the video!
My left ear liked this one
Sorry about that😁
First off, major respect for that technician for taking the scantool home to learn how to use it, and equally major respect for the manager for encouraging it. That kind of initiative and support is rare these days!
That was quite a twist! I run into tuned PCM issues every so often, but I've never had a no-start before, usually just that I can't program other modules because of it.
I don't know if there's a name for that phenomenon where stored/history codes keep an otherwise functioning system disabled; I call it "code holding." It is THE most annoying thing to deal with, and I'm seeing it more and more. Toyota has gotten really bad about it in the last 2-3 years.
Excellent video. Thank you.
Glad you enjoyed it! 👍
Oh my God. It was the owner who srewed up with a new software..... the patience and systematic work of yours finally pegged it down.....it was such a difficult , almost impossible work task since the diagnostic could not show what was wrong due to altered ECM software....Hats off to you Mr.Diagnose Dan for taking in the work and proceeding step by step, explaining them , and sharing ,and teaching us the perils of ECM mods. God bless..
I really appreciate your detailed comment and your appreciation for the systematic approach! Thanks for watching! 👍
Another brilliant video- I had absolutely no idea a remap can cause these issues! Well done
It must be my near total lack of experience and knowledge, but I've always had this idea in my head that messing with the software in a computerized modern vehicle is a disaster waiting to happen. If you want a more powerful car, buy a more powerful car, I say.
He’s a tech and his spark plugs look like that !
getting every last euro outa them plugs not my car btw
Obviously a rookie as he's wanting to learn the tool (which is to be commended), but even a slightly enthused car guy would look after his car better than that.
He's a body shop guy, they probably only bought the scan tool to reset the codes that gets created when the collision detection or parking monitors etc. have been damaged or need to be unplugged n plugged back in.
Body Shop😁
This was not only a great example of trouble shooting technique, it’s also an example of how easy it is to go down a rabbit hole. Sometimes it’s good to walk away and start fresh.
I’m this case you nailed it, you we captivated by a good story and got a preconceived notion of what the problem might be resulting in missing something important. This happens to even the best and shows how important keeping an open mind is.
The funny thing is that a new ECU would have fixed the problem and the blame would have been put on the scan tool.
Great video!
Every episode is a masterclass in automotive diagnostics.
Thank you very much for the positive feedback!
Great diagnostics Dan, from a retired mechanic in the UK.
Much appreciated! Always great to hear from fellow mechanics even if they are retired👍
@Diagnosedanretired from working. Except at home doing my friends cars 😂😂
Ottimo lavoro ...il video è stato molto interessante, 😀👍
Thanks!
Boy, I do not like the fact that the PCM will not allow the engine to run until fault codes are erased !! That is not a good idea in my opinion.
Well, the owner must have done something to mess up his performance tune software. He is likely better off without it anyway.
Good diagnosis, Dan. That one would be tough for many technicians especially not knowing the PCM was altered.
It definitely adds an extra layer of complexity when you're dealing with altered PCM software!
Congratulations.. regards from Athens Greece...😊
Thanks for watching all the way from Greece! 😊
Oh boy, what a headache! I wasn't aware they inhibit alarms during the tuning, that explains a lot.
Basically the engine is not only squeezed but also silenced. Not the engineering way
You have to patch certain errors or change thresholds. Because tuned engine is producting values that give errors on stock ecu
Quite common in "poor man" tuning services in Eastern EU, Russia, Etc when they try change maps drastically on stock OEM modules. You see almost 20 year old sporty car with no codes? Yeah... When I heard that there are no error codes at all on this Renault my first bet would be to check the maps and software :D
I enjoyed your video! Something worth watching on YT
Thanks for watching! 😊
Dan makes a mistake by taking on a vehicle he wouldn’t touch, turns out to still be a very useful video giving us an insight into what custom tunes/remaps do.
Another great video Dan 👍
Sometimes even mistakes lead to valuable lessons. Thanks for the kind words!
11:37 I love it when all mechanics myself included love this badge. ofc, all the ones related to it as well
😂
Another great video, Dan. Hello again from Manitoba Canada!
Thanks for watching all the way from Canada! Glad you liked it! 👍