@kelectr0n The VENT valve is an easy DTC to repair. There is a big chance that your VENT DTC is related to an electrical problem, such as an open or short. Disconnect the vent valve (solenoid) towards the rear of the vehicle and check with a multimeter. You're looking for a broken coil winding, broken wire or a short.
You now need to actuate and inflate the EVAP system. You also need to monitor the LDP reed switch while inflating or pressurizing the EVAP system. It is somewhat complicated and the best way to do this is using the factory Dodge scan tool, but it can be done manually.
If you close the VENT all the time, the fuel tank would inflate or create suction as fuel is used. The fuel tank has to breathe. Vent valve is closed to run the EVAP monitor (test) and detect fuel vapor leaks. Makes sense.
@kelectr0n It is very odd that you'd get a DTC related to electrical and the cause being a performance problem. Keep in mind this: The ECM looks at the return voltage from the vent valve ground wire at all times. If just for an instant this voltage is lost, such DTC is generated. Resistance in the wires is also a problem. I rarely recommend it, but at this time I would erase the DTC and drive the vehicle a bit to see if the same DTC is generated.
No, fuel pressure sensors do regulate pressure to some extent, but there's also a mechanical pressure regulator at the tank. High fuel pressure can be caused by a defecting regulator, even on returnless systems where the regulator is inside the tank. However, all these scenarios are rare. Make sure you check that the gauge is working properly. that's why I recommend a pressure transducer. check my series on "MYODE, Make Your Own Diagnostic Equipment". thank you.
Cont... If dirt or fuel gum deposits prevent the float ball from returning to its open position, it'll cause exactly the problem you're having. Your issue is somewhere between the gas cap and the fuel tank. You may have to dismantle a few plastic panels to expose this fuel-fuller mechanism. Then remove and clean thoroughly if you know how to work with gasoline components or show your mechanic.
@kelectr0n Yes, very very good. Good logic. But hear this, DTC P0449 is a control circuit or code relating to the circuit. This means either open or short circuit. Also a problem to the power feed or ground. What you're describing is a performance problem, such as a broken hose, etc.
Thank you. Yes, you make good points about using different voices. Very interesting and may use some of that on a new series I'm working on. Thanks again...
@ADPTraining CONTINUED: If this happens right away then it is definitely an electrical fault. If it takes a while for the DTC to set, then either the electrical fault is not present at all times or it is related to vibrations or loose connections. Keep me posted. Good luck.
Well, it is a pesky code but will not make the car leave you stranded. Your Neon uses an LDP pump. Follow the large hose that leaves the LDP pump to the rear of the vehicle or the charcoal canister. Try and isolate the small leak. Driving around with scanner connected will not help you. Do not erase codes. You may find leak by crimping the fuel vapor hoses, pressurizing the system with 1/4 PSI and see if still leaks. It is a hard job to do but not impossible. good luck...
Ok, your evap is probably sharing a reference voltage with another sensor. It is for example common on older Cadillacs to for the transmission not to shift when the air-conditioning high pressure sensor shorted out. Disconnect the EVAP connection you did and see what happens. Post back with more to get to the issue at hand...Thanks
@ADPTraining CONTINUED: I would look for a wiring or electrical problem. Almost all OBD-2 DTCs (codes) are either performance or electrical codes. If your DTC was relates to that broken elbow then I think you'd be seeing a performance DTC, as in VENT VALVE LEAK or something like that. The cornerstone of OBD2 diagnostics is identifying whether it's an electrical or performance DTC. Let me know and good luck...
There was a fellow posting a comment on his Eclipse, with symptom of having a hard time filling up with gas. Sorry, I accidentally erased your comment. Please, post again. Here is the possible problem: All modern vehicles have an anti-vapor gas filling system. This is a purely mechanical system, using a float ball valve within the filler neck or closer to the fuel tank.
That sounds like a plan. The issue is what about our gay viewers and the ladies that watch our videos. We are an all inclusive channel. We approve, support and respect everyone. I would like to find an African American voice-over, but so far no luck. We support all our viewers equally.
You have a purge flow issue. Check purge solenoid and hoses first at the engine compartment. See our video on the matter. Learn the system and do some simple diagnostics. You can do this and save lots of money. Regardless, FORGET DEALER, as they're not a repair shop. Dealerships sell cars, not repair them. They just change all the parts. Get yourself a goo INDEPENDENT REPAIR SHOP and go with it, if you can't do it yourself. Good luck.
Yes, but the risk of explosion is none. Why? Because there's almost no Oxigen inside the tank or EVAP system. Now that you have a hole on the system then you have to watch out. About the backfire from the engine, YES you're right. BF tend to cause all kinds of issues with connected components.
@FxXSMALLSXxF Thanks so much for posting. You need stress the circuit. A TL is the least load device you can use to test any ECM circuit. A mutimeter is used to test electronic issues, not electrical problems. Good luck.
My 2006 Chevy Equinox has a P0171 lean bank 1 code, which may indicate a vacuum leak somewhere. I think it's in the EVAP system because my scanner shows the EVAP system check as being incomplete.
I have 98 Isuzu Rodeo, the problem is that a few weeks ago the Check Engine will come on with code PO440 (EVAP). The problem is a leak in the EVAP system, you change the gas cap, tighten the hose to the EVAP system, but the light comes every time the gas tank is just a half, I have checked and all information indicates that there is faulty pump gasoline. But I'm not sure what to do.
I agree, although the African American voice will be nice but if you can find a German or Russian voice that will be Funny And Great, I think that yo will find some users online who will be more than happy to read the script for you, any way, Just Keep Your GREAT WORK up.AND on behalf on lots of Users Big THANKS.
@FxXSMALLSXxF Hello, thanks so much for posting. Your assertion is wrong. You use a mutimeter for many things ECM, but to stress a circuit, as in proving a power or a ground circuit you use a test light. A regular incandescent test-light draws a nominal 300mA, enough to stress a small circuit. In other cases you may even have to use a higher load, as a head light substitution. When proving a false ground, if you don't use a test light you'll never find a 10 Ohm resistance, which will cause havoc
So i just pulled my charcoal canister off my 2006 pathfinder and ohmed out the solenoid at 700-800 ohms...and is their a fuse or another spot i can yest for voltage back ? As it stands i cant really check voltage where it is...
That's a general EVAP leak code. You have a long way to go before condemning the LDP pump. I have other more precise LDP and EVAP system videos that may help you. Post back with more...
I recently had an EVAP canister blow up! It had a huge crack, the pipe to the tank snapped and the valve had been blown out of it. Potentially dangerous as fuel vapour is very volatile. Im thinking a back fire in the inlet manifold caused this, any thoughts?
can a faulty lpd stall your vehicle ? at times my vehicle stalls , the only code in my car is a po455 or can it be fuel related as per fuel pump or fuel pump regulator ? it;s a 1999 mitsu eclipse 2.0 nt
It looks simple and layout on the computer but when I looked under my car, everything is compact. I still can't fix a code P0446 something about the vent control. Can anyone help me?
I have a 2003 Chevrolet S10 2.2 and keep getting the P0440 code. It happens very intermittently the gas cap has been replaced and still get the code but it has happened as quickly as 25 miles and has also gone close to 200 miles before reappearing. any ideas?
This EVAP issue is not easy to tackle. Here's all the help you could possibly need. It is a download. www.autodiagnosticsandpublishing.com/Automotive_Actuator_Testing_PDF.html
EVAP Purge valves are almost always located near the intake manifold. It is however scattered around the engine compartment on different models. Look for a 1/4 to 1/2 inch vacuum hose and follow it. Hope that helps/
p0456 code has been coming on for my 2001 dodge neon for so long now I am ready to just straight blow my car up....... Currently driving around with Diagnostic Machine connected to my car in hopes of code clearing soon. anybody got any idea how to fix this problem
take it to car dealer ,they will charge 150 just to do so ,then theyll charge u for smoking the car and last but not least the price to fix ,like 700 ...rip offs!
You Know , as you use the E-Voice any way , why don't you try to make it in a women voice, personally i like when ladies talk about cars, thumps up guys if you like the idea
@kelectr0n The VENT valve is an easy DTC to repair. There is a big chance that your VENT DTC is related to an electrical problem, such as an open or short. Disconnect the vent valve (solenoid) towards the rear of the vehicle and check with a multimeter. You're looking for a broken coil winding, broken wire or a short.
I hope the vac you um doesn't drop too fast there, Mr Computervoice.
You now need to actuate and inflate the EVAP system. You also need to monitor the LDP reed switch while inflating or pressurizing the EVAP system. It is somewhat complicated and the best way to do this is using the factory Dodge scan tool, but it can be done manually.
That's why we have this channel and I've published various books on the subject, TO SAVE you money. Thank you.
If you close the VENT all the time, the fuel tank would inflate or create suction as fuel is used. The fuel tank has to breathe. Vent valve is closed to run the EVAP monitor (test) and detect fuel vapor leaks. Makes sense.
@kelectr0n It is very odd that you'd get a DTC related to electrical and the cause being a performance problem. Keep in mind this: The ECM looks at the return voltage from the vent valve ground wire at all times. If just for an instant this voltage is lost, such DTC is generated. Resistance in the wires is also a problem.
I rarely recommend it, but at this time I would erase the DTC and drive the vehicle a bit to see if the same DTC is generated.
No, fuel pressure sensors do regulate pressure to some extent, but there's also a mechanical pressure regulator at the tank. High fuel pressure can be caused by a defecting regulator, even on returnless systems where the regulator is inside the tank. However, all these scenarios are rare. Make sure you check that the gauge is working properly. that's why I recommend a pressure transducer. check my series on "MYODE, Make Your Own Diagnostic Equipment". thank you.
Cont...
If dirt or fuel gum deposits prevent the float ball from returning to its open position, it'll cause exactly the problem you're having.
Your issue is somewhere between the gas cap and the fuel tank. You may have to dismantle a few plastic panels to expose this fuel-fuller mechanism. Then remove and clean thoroughly if you know how to work with gasoline components or show your mechanic.
@kelectr0n Yes, very very good. Good logic. But hear this, DTC P0449 is a control circuit or code relating to the circuit. This means either open or short circuit. Also a problem to the power feed or ground. What you're describing is a performance problem, such as a broken hose, etc.
Thank you. Yes, you make good points about using different voices. Very interesting and may use some of that on a new series I'm working on. Thanks again...
@ADPTraining CONTINUED: If this happens right away then it is definitely an electrical fault. If it takes a while for the DTC to set, then either the electrical fault is not present at all times or it is related to vibrations or loose connections. Keep me posted. Good luck.
Well, it is a pesky code but will not make the car leave you stranded. Your Neon uses an LDP pump. Follow the large hose that leaves the LDP pump to the rear of the vehicle or the charcoal canister. Try and isolate the small leak. Driving around with scanner connected will not help you. Do not erase codes. You may find leak by crimping the fuel vapor hoses, pressurizing the system with 1/4 PSI and see if still leaks. It is a hard job to do but not impossible. good luck...
Ok, your evap is probably sharing a reference voltage with another sensor. It is for example common on older Cadillacs to for the transmission not to shift when the air-conditioning high pressure sensor shorted out. Disconnect the EVAP connection you did and see what happens. Post back with more to get to the issue at hand...Thanks
@ADPTraining CONTINUED:
I would look for a wiring or electrical problem. Almost all OBD-2 DTCs (codes) are either performance or electrical codes. If your DTC was relates to that broken elbow then I think you'd be seeing a performance DTC, as in VENT VALVE LEAK or something like that. The cornerstone of OBD2 diagnostics is identifying whether it's an electrical or performance DTC. Let me know and good luck...
There was a fellow posting a comment on his Eclipse, with symptom of having a hard time filling up with gas. Sorry, I accidentally erased your comment. Please, post again. Here is the possible problem:
All modern vehicles have an anti-vapor gas filling system. This is a purely mechanical system, using a float ball valve within the filler neck or closer to the fuel tank.
P0443 is what mechanic told me Evap Vent Control total cost 160 he says, but read on line a lot of times somethings just loose and needs tighting
That sounds like a plan. The issue is what about our gay viewers and the ladies that watch our videos. We are an all inclusive channel. We approve, support and respect everyone. I would like to find an African American voice-over, but so far no luck. We support all our viewers equally.
Good video and theory of operation .
You have a purge flow issue. Check purge solenoid and hoses first at the engine compartment. See our video on the matter. Learn the system and do some simple diagnostics. You can do this and save lots of money. Regardless, FORGET DEALER, as they're not a repair shop. Dealerships sell cars, not repair them. They just change all the parts. Get yourself a goo INDEPENDENT REPAIR SHOP and go with it, if you can't do it yourself. Good luck.
Yes, but the risk of explosion is none. Why? Because there's almost no Oxigen inside the tank or EVAP system. Now that you have a hole on the system then you have to watch out. About the backfire from the engine, YES you're right. BF tend to cause all kinds of issues with connected components.
Cont 2 ...
This is a little known set of components, whose issues often times go unresolved by some repair shops. Good luck...
@FxXSMALLSXxF Thanks so much for posting. You need stress the circuit. A TL is the least load device you can use to test any ECM circuit. A mutimeter is used to test electronic issues, not electrical problems. Good luck.
I've changed the gas cap and #1 hose on the canister which had 2 cracks in it
Why soldier, once humanity destroys itself, robots will be the only thing left. Thanks for posting.
Thanks so much for sharing...
My 2006 Chevy Equinox has a P0171 lean bank 1 code, which may indicate a vacuum leak somewhere. I think it's in the EVAP system because my scanner shows the EVAP system check as being incomplete.
I have 98 Isuzu Rodeo, the problem is that a few weeks ago the Check Engine will come on with code PO440 (EVAP). The problem is a leak in the EVAP system, you change the gas cap, tighten the hose to the EVAP system, but the light comes every time the gas tank is just a half, I have checked and all information indicates that there is faulty pump gasoline. But I'm not sure what to do.
great Video , lots of very useful info, Thanks man , Keep it Up
I agree, although the African American voice will be nice but if you can find a German or Russian voice that will be Funny And Great, I think that yo will find some users online who will be more than happy to read the script for you, any way, Just Keep Your GREAT WORK up.AND on behalf on lots of Users Big THANKS.
@FxXSMALLSXxF Hello, thanks so much for posting. Your assertion is wrong. You use a mutimeter for many things ECM, but to stress a circuit, as in proving a power or a ground circuit you use a test light. A regular incandescent test-light draws a nominal 300mA, enough to stress a small circuit. In other cases you may even have to use a higher load, as a head light substitution. When proving a false ground, if you don't use a test light you'll never find a 10 Ohm resistance, which will cause havoc
I've replaced the gas cap and hose #1 on the EVAP Canister which had 2 cracks in it and the light is still on
If not the canister vent valve solenoid, would a defective fuel pressure sensor cause high fuel pressure?
Thank you for posting
Can a bad canister vent valve solenoid cause high fuel pressure?
ok sir
So i just pulled my charcoal canister off my 2006 pathfinder and ohmed out the solenoid at 700-800 ohms...and is their a fuse or another spot i can yest for voltage back ? As it stands i cant really check voltage where it is...
hi, why vent valve is opened all the time except purging. means why we cant close the vent valve all time, i dont know why it is normally opened.
have a 2004 dodge neon and got the code p0440 and p0441 pop up but not really sure what the problem is. Not really trying to go a dealership either.
p0455 is my problem. cant find anything for a fix. i guess a $75 diagnostic fee is what i'll have to be paying.
You are welcome
I have a p0440 code on my engine. Do evap codes actually cause problems in the performance of my vehicle? Or is it more for environmental awareness?
That's a general EVAP leak code. You have a long way to go before condemning the LDP pump. I have other more precise LDP and EVAP system videos that may help you. Post back with more...
I've got a 2003 Dodge Neon with P0456....what's the chances of the LDP Pump being bad?
I recently had an EVAP canister blow up! It had a huge crack, the pipe to the tank snapped and the valve had been blown out of it. Potentially dangerous as fuel vapour is very volatile. Im thinking a back fire in the inlet manifold caused this, any thoughts?
can a faulty lpd stall your vehicle ? at times my vehicle stalls , the only code in my car is a po455 or can it be fuel related as per fuel pump or fuel pump regulator ? it;s a 1999 mitsu eclipse 2.0 nt
ty
It looks simple and layout on the computer but when I looked under my car, everything is compact. I still can't fix a code P0446 something about the vent control. Can anyone help me?
my Evap sensor is clicking sometimes and sometimes dont
I have a 2003 Chevrolet S10 2.2 and keep getting the P0440 code. It happens very intermittently the gas cap has been replaced and still get the code but it has happened as quickly as 25 miles and has also gone close to 200 miles before reappearing. any ideas?
This EVAP issue is not easy to tackle. Here's all the help you could possibly need. It is a download.
www.autodiagnosticsandpublishing.com/Automotive_Actuator_Testing_PDF.html
does any one know the location of the EVAP purge solenoid valve, on a 1990 300zx, non turbo? thanks
EVAP Purge valves are almost always located near the intake manifold. It is however scattered around the engine compartment on different models. Look for a 1/4 to 1/2 inch vacuum hose and follow it. Hope that helps/
p0456 code has been coming on for my 2001 dodge neon for so long now I am ready to just straight blow my car up....... Currently driving around with Diagnostic Machine connected to my car in hopes of code clearing soon. anybody got any idea how to fix this problem
This video has great information but the computer voice makes it very hard to pay attention to what is trying to be taught.
I'm a computer
things to get that extra .05mpg
it not a veh rey beh sic one.. thevery basic one has no solenoid
Thanks, It's not Steven... it's Arnold Schwarzenegger... I'll be back.
Too bad I couldnt even figured wtf is hoing on in this video
DONT USE A TEST LIGHT ON ECM CIRCUITS. You will jack sh!t up. Use a multimeter
take it to car dealer ,they will charge 150 just to do so ,then theyll charge u for smoking the car and last but not least the price to fix ,like 700 ...rip offs!
what the hel is a vacuuhueum
Vac-u-um...LOL
You Know , as you use the E-Voice any way , why don't you try to make it in a women voice, personally i like when ladies talk about cars, thumps up guys if you like the idea
Sorry, different ideas I have found about evap
Do you mind sharing your ideas?...
hate the robot voice