Thanks for watching. Have you experienced any engine idle rpm fluctuations? More videos like this here: ruclips.net/p/PLmgCmljtdCzWMExyPXgSeeJZYwOA1Ocj7
im experiencing something like this ..when I start my bike the idle is up and down for the first minute or so but then idles fine. it fluctuates up and then down to almost a stall but then it catches itself and goes back up ???
The short version if the idle is all over the map, There is the motor temp sensor on the harley that love to go south, you have the intake seals that love to dry out and shrink, and then we have the IAC that is trying to keep the idle steady on the drop from high idle on a cold motor, to down to normal idle speed as the motor does come up the temp. Also to point out, ECM runs the motor richer at start up, until the motor does come up to speed, then then drops the fuel mixture can down to it leaner conditions. So out the gate, really need to replace the intake manifold seal to start with if the bike does have a few years on it due to them shrinking from the heat. When you go to install the new seals, use dielectric grease to grease the seals inside and out,. Granted that the fuel through the seals surfaces that the fuel can get to will remove the grease on the seals, but where the fuel does not get to, the dielectric grease will allow the seals to last years longer before they dry out and shrink instead. Note, if you are starting to get decel pop that you never had before, did not change the tune in any way, then TB seals are leaking. Next in line is the engine temp sensor. Hence it going to start going south long before the it starts throwing code. Let me put it this way, and if you have the motor up to temp, but getting fast idles at say a stop lights and the TB seal are not leaking, its the engine temp sensor. Again, ECM is checking the temp sensor to see the engine heat, and if the sensor is reading lower than what the motor really is, then ECM is increasing the idle speed via the IAC, and well as kicking back to the richer AFR tables. Here is the glitch on checking the motor temp verse sensor temp reading at the ECM, since most scanner for the Harley are not cheap. So without scanner to use a thermal gun on the head, verses what the sensor is reading the quick way, then need to pull the sensor, and check it's resistance in water that is just starting to boil. Hence water boils at 212*, and if you check your manual, will give resistance value for your sensor at that temp (should be right around 204 ohms at 212*, with a base line of 526 ohms at 70*). Note base line cold is not what we are checking but what that the ohm reading does drop down to the correct ohm reading at 212* of when the water did first start to boil. As for not even having to check the sensor in water with the motor hot, just pull off your air filter cover, and look at the arm on the TB linkage at the fast idle screw location. Hence will have the high idle screw on the right hand side of the TB, and that piece that the allen head high idle screw bolts to, IAC should have pulled all the way up off the lower linkage set screw point once the motor comes up to temp. If the arm is still dancing to pull the idle back up, then its the ET that is not reading correctly, causing the ECM to control the motor idle like it still cold isntead. This pretty much covers the old MM bikes that only run in open loop, but on the newer bikes that are working in closed loop, Really need to put it on a scanner after you have check the TB seals. Hence any one of the close loop sensors not reading correctly, will have the ECM using the IAC to try to keep the motor running. Note, when the motor is cold, it's running in open loop, due to the fact that the ECM does have the motor running on the cold richer AFR tables. Once the engine comes up to heat (via ET sensor), then will kick the down to the normal lean tables, and again, IAC should have check out of play as well. So first check when idle is all over the map at stay a stop light with motor up to temp, just look at the high idle screw piece/IAC, and if the two are still in play, you have a sensor that is causing problems. Hence once the motor is up to temp, should have about a turn out distance of end of the high idle screw end, and the block part that it touches to pull the idle up.
I'm checking my bike, an aprilia rsv 04, the idle is a little hunting at 14xx-13xx. hope it not ecu, vaccum, or mapping probs. Need to understand more on idle and your video really helps.
Yes ive got a 2006 roadking custom..now very fast idling and thrown a po505 error idle code ..think it's the iac unit after cleaning the throttle intake ..but maybe seals vacuum leak ??
Thanks for the info. I have a Harley Davidson Electra Glide I think I’m gonna start by checking my temperature sensor. I’m having trouble went I stop at the red light, for some reason my engine RPMs rise a bit and it goes down went I hit the throttle.
I had this issue on my Low Rider. Even when warm at a stop the rpm would shoot up from 1000 rpm or so up to 1500 and above and then back down again. I was so concerned I took it to the dealer. They hooked it up to their computer and test rode it, no issues found. I was told it is normal on the M8's to do this. I was not convinced! Anyhow I later learnt my engine management system (rear cylinder shut off) was in the off position so I put it into the on position and that seemed to sort out the problem. I also think it had something to do with my bike only having done a 100 miles or so, maybe. Thanks.
Just got my 2020 Fat Boy and it seems to be Idling Low between 810 to 840. Seems to be no way to bring it up aside from bringing it in for a tune but here in china the dealer seems to not be to knowledgeable about it at all and expects me to leave it in shop for 2 to 3 weeks.
Yes good morning yes I have a Softail Deluxe 2016 on my RPM when I get ready to start the bike the numbers are already at 1000 and above when I get to 3rd gear 4th gear my RPM numbers are at 28 to 3100
I think of the system as an automatic choke, for those that remember them. I think in hot engine conditions the engine management system also cuts of ignition and possibly fuel to the rear cylinder, not happend to me yet but its not that hot here this time of year, or ever.
Another great vid! My 21 Sport glide idles fine on startup and slowly reduces as youd expect. However, once hot, it idles in a kind of wave type fashion between low 700's and 1000 rpm. Its my first Harley but this can't be normal? When the eitms kicks in, it levels off at around 1000 and seems to operate as designed, but it's when the eitms isn't activated that concerns me. Any ideas? Thanks!
It could be that one of your sensors is not operating properly such as the ET sensor however that being said if it’s not too bad I’d live with it for now and see how it develops in the coming months
@@RevelatorAlf Thanks for your reply! It doesn't seem too bad but does sound odd jumping up & down at idle when stopped at lights. Cheers for so many informative vids...much better than a manual 😀👍🏼
@@Big-Daddy96 Cheers! Dealer took mine in a few months back and said the idle was normal (not saying I agree with them). Mine has to be hot and doesn't do it all the time. When I take it in for service I'm going to make sure it happens in front of them and see what they think.
I had RPM hunting on a 2019 Milwaukee 8. The dealer kept it 30 days. They finally changed a sensor and delivered the bike to me. I've since traded for a 2020 with RDRS so I don't know the long term result of their repair.
@@flyingjeff1984 Ah Ok great, yes that would make sense but I wonder if both sensors and all 4 spark plugs were faulty. Be in any case thanks for the info. Cheers
@@RevelatorAlf I found it interesting that no part number was listed for the TMAP sensor. And when was the last time you came across a faulty spark plug on a nearly new bike? Possibly never.
Yes I think your mapping will need just a little more tweaking if that is the case. No the hunting can occur on stock bikes too so not sure that's totally correct.
@@RevelatorAlf ah ok. Let me make a few more km's on it haha. I did buy the dealers demo bike. (otherwise eu stock would be filled up on the end of January) So allot of people have ridden it. I think that has something to do with it to. But the guarantee is still there and the dealer did the stage 1 so also covered by the guarantee. In 500 km's I'm at 1600 so first big service is almost there. After that I'll see. Cheers.
My 300 parallel twin when idle fluctuates +or-100 rpm always, and when I notice it very carefully, I feel the engine shocks are uneven (mild uneven vibrations felt only when carefully observed by touching the engine). Done around 6000 kms. Is this something to be worried about?
Mine fluctuates when cold between 1450 rpm down to 1000 back up to 1400 for about a minute. Do u have any idea what could cause this during warm up only ?
Yes I would say that’s quite normal depending on your temperatures and how your ecm is assuring the starting but if in doubt go get it checked out for sure.
OK this could be a host of reasons. Check your sensors e.g ET, TMAP, CKP etc as these are feeding info into ECM which could cause it to drive your RPMs low. Recycle your EITMS too and see if that works. If your engine cuts out in neutral but still has normal RPMs then check your kick stand (jiffy) sensor switch too. Hope this helps
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Thanks for watching. Have you experienced any engine idle rpm fluctuations? More videos like this here: ruclips.net/p/PLmgCmljtdCzWMExyPXgSeeJZYwOA1Ocj7
im experiencing something like this ..when I start my bike the idle is up and down for the first minute or so but then idles fine. it fluctuates up and then down to almost a stall but then it catches itself and goes back up ???
The short version if the idle is all over the map, There is the motor temp sensor on the harley that love to go south, you have the intake seals that love to dry out and shrink, and then we have the IAC that is trying to keep the idle steady on the drop from high idle on a cold motor, to down to normal idle speed as the motor does come up the temp. Also to point out, ECM runs the motor richer at start up, until the motor does come up to speed, then then drops the fuel mixture can down to it leaner conditions.
So out the gate, really need to replace the intake manifold seal to start with if the bike does have a few years on it due to them shrinking from the heat. When you go to install the new seals, use dielectric grease to grease the seals inside and out,. Granted that the fuel through the seals surfaces that the fuel can get to will remove the grease on the seals, but where the fuel does not get to, the dielectric grease will allow the seals to last years longer before they dry out and shrink instead.
Note, if you are starting to get decel pop that you never had before, did not change the tune in any way, then TB seals are leaking.
Next in line is the engine temp sensor. Hence it going to start going south long before the it starts throwing code. Let me put it this way, and if you have the motor up to temp, but getting fast idles at say a stop lights and the TB seal are not leaking, its the engine temp sensor. Again, ECM is checking the temp sensor to see the engine heat, and if the sensor is reading lower than what the motor really is, then ECM is increasing the idle speed via the IAC, and well as kicking back to the richer AFR tables. Here is the glitch on checking the motor temp verse sensor temp reading at the ECM, since most scanner for the Harley are not cheap. So without scanner to use a thermal gun on the head, verses what the sensor is reading the quick way, then need to pull the sensor, and check it's resistance in water that is just starting to boil. Hence water boils at 212*, and if you check your manual, will give resistance value for your sensor at that temp (should be right around 204 ohms at 212*, with a base line of 526 ohms at 70*).
Note base line cold is not what we are checking but what that the ohm reading does drop down to the correct ohm reading at 212* of when the water did first start to boil.
As for not even having to check the sensor in water with the motor hot, just pull off your air filter cover, and look at the arm on the TB linkage at the fast idle screw location. Hence will have the high idle screw on the right hand side of the TB, and that piece that the allen head high idle screw bolts to, IAC should have pulled all the way up off the lower linkage set screw point once the motor comes up to temp. If the arm is still dancing to pull the idle back up, then its the ET that is not reading correctly, causing the ECM to control the motor idle like it still cold isntead.
This pretty much covers the old MM bikes that only run in open loop, but on the newer bikes that are working in closed loop, Really need to put it on a scanner after you have check the TB seals. Hence any one of the close loop sensors not reading correctly, will have the ECM using the IAC to try to keep the motor running.
Note, when the motor is cold, it's running in open loop, due to the fact that the ECM does have the motor running on the cold richer AFR tables. Once the engine comes up to heat (via ET sensor), then will kick the down to the normal lean tables, and again, IAC should have check out of play as well. So first check when idle is all over the map at stay a stop light with motor up to temp, just look at the high idle screw piece/IAC, and if the two are still in play, you have a sensor that is causing problems. Hence once the motor is up to temp, should have about a turn out distance of end of the high idle screw end, and the block part that it touches to pull the idle up.
Cheers for that info. Great stuff
I'm checking my bike, an aprilia rsv 04, the idle is a little hunting at 14xx-13xx. hope it not ecu, vaccum, or mapping probs. Need to understand more on idle and your video really helps.
My 2020 sport glide with retimed ShortShots exhausts starts at about 1400 and slows down to 720/860 feels more relaxed and sounds nicer
Yes ive got a 2006 roadking custom..now very fast idling and thrown a po505 error idle code ..think it's the iac unit after cleaning the throttle intake ..but maybe seals vacuum leak ??
Thanks for the info. I have a Harley Davidson Electra Glide I think I’m gonna start by checking my temperature sensor. I’m having trouble went I stop at the red light, for some reason my engine RPMs rise a bit and it goes down went I hit the throttle.
I had this issue on my Low Rider. Even when warm at a stop the rpm would shoot up from 1000 rpm or so up to 1500 and above and then back down again. I was so concerned I took it to the dealer. They hooked it up to their computer and test rode it, no issues found. I was told it is normal on the M8's to do this. I was not convinced! Anyhow I later learnt my engine management system (rear cylinder shut off) was in the off position so I put it into the on position and that seemed to sort out the problem. I also think it had something to do with my bike only having done a 100 miles or so, maybe. Thanks.
mark henry yes sounds about right. Cheers
Just got my 2020 Fat Boy and it seems to be Idling Low between 810 to 840. Seems to be no way to bring it up aside from bringing it in for a tune but here in china the dealer seems to not be to knowledgeable about it at all and expects me to leave it in shop for 2 to 3 weeks.
Yes good morning yes I have a Softail Deluxe 2016 on my RPM when I get ready to start the bike the numbers are already at 1000 and above when I get to 3rd gear 4th gear my RPM numbers are at 28 to 3100
Please can you inbox me on Facebook at MIS L minnis
It’s probably best if you email me via the website and give me a full description of what you are seeing. Thanks
I think of the system as an automatic choke, for those that remember them. I think in hot engine conditions the engine management system also cuts of ignition and possibly fuel to the rear cylinder, not happend to me yet but its not that hot here this time of year, or ever.
Stephen Fleming yes that’s essentially what it is cheers
I think this is the issue with my bike. It’s got a starting issue. And I think it’s related to the cold start and the throttle body.
Thanks help alot.
I have a softail 2008 can I reduce the rpm to 900 after it warms up
Another great vid!
My 21 Sport glide idles fine on startup and slowly reduces as youd expect. However, once hot, it idles in a kind of wave type fashion between low 700's and 1000 rpm. Its my first Harley but this can't be normal?
When the eitms kicks in, it levels off at around 1000 and seems to operate as designed, but it's when the eitms isn't activated that concerns me. Any ideas? Thanks!
It could be that one of your sensors is not operating properly such as the ET sensor however that being said if it’s not too bad I’d live with it for now and see how it develops in the coming months
@@RevelatorAlf Thanks for your reply! It doesn't seem too bad but does sound odd jumping up & down at idle when stopped at lights.
Cheers for so many informative vids...much better than a manual 😀👍🏼
I have the same issue on my low rider except I jump from 600s to 1000s. Finally got the dealer to look at it I'll post their findings
@@Big-Daddy96 Cheers! Dealer took mine in a few months back and said the idle was normal (not saying I agree with them). Mine has to be hot and doesn't do it all the time. When I take it in for service I'm going to make sure it happens in front of them and see what they think.
I had RPM hunting on a 2019 Milwaukee 8. The dealer kept it 30 days. They finally changed a sensor and delivered the bike to me.
I've since traded for a 2020 with RDRS so I don't know the long term result of their repair.
Ah ok. Do you know which sensor they changed? Cheers
@@RevelatorAlf TMAP Sensor and Temp Sensor (32700065). No part number listed for TMAP Sensor. Also 4 new spark plugs.
@@flyingjeff1984 Ah Ok great, yes that would make sense but I wonder if both sensors and all 4 spark plugs were faulty. Be in any case thanks for the info. Cheers
@@RevelatorAlf I found it interesting that no part number was listed for the TMAP sensor. And when was the last time you came across a faulty spark plug on a nearly new bike? Possibly never.
thanks great tip
No problem! Cheers
My Sport Glide 2020 its between 850 and 950 with hot engine, and around 1250 at first start (stock exhaust).
Yes sounds about correct. Cheers
mine is hunting when warm. its cause of the tuning and the stage 1 they tell me. also the O2 error keeps comming back and going away
Yes I think your mapping will need just a little more tweaking if that is the case. No the hunting can occur on stock bikes too so not sure that's totally correct.
@@RevelatorAlf ah ok. Let me make a few more km's on it haha. I did buy the dealers demo bike. (otherwise eu stock would be filled up on the end of January) So allot of people have ridden it. I think that has something to do with it to. But the guarantee is still there and the dealer did the stage 1 so also covered by the guarantee. In 500 km's I'm at 1600 so first big service is almost there. After that I'll see.
Cheers.
Ok sure. Let us know how you get on. Cheers
My 300 parallel twin when idle fluctuates +or-100 rpm always, and when I notice it very carefully, I feel the engine shocks are uneven (mild uneven vibrations felt only when carefully observed by touching the engine). Done around 6000 kms. Is this something to be worried about?
It may need a checking over as there could be a discrepancy between the two cylinders
RevelatorAlf thanks you so much. Your videos are very informative
Mine fluctuates when cold between 1450 rpm down to 1000 back up to 1400 for about a minute. Do u have any idea what could cause this during warm up only ?
Yes I would say that’s quite normal depending on your temperatures and how your ecm is assuring the starting but if in doubt go get it checked out for sure.
What the heck does hunting mean when referencing a Harley engine?
RPM not stabilising
Boss my fatboy idling up and down and it turns off in neutral
OK this could be a host of reasons. Check your sensors e.g ET, TMAP, CKP etc as these are feeding info into ECM which could cause it to drive your RPMs low. Recycle your EITMS too and see if that works. If your engine cuts out in neutral but still has normal RPMs then check your kick stand (jiffy) sensor switch too. Hope this helps
Ever find a solution to this?