Hi all
After some ideas on a very intermittent problem we have with my wife's 2013 Slim.
Problem started 18 months ago for no real apparent reason. Bike would start idling either fast (up to 1700rpm) or low to to point of stalling. Usually it would idle fast when downshifting and stopping at lights, then it would switch to very low idle and stall. Misfiring and carrying on. If we were on a ride and stopped for a 45min drinks break it would not restart without cranking the throttle wide open. Plumes of black smoke would billow. Next few times riding there would not be the slightest issue. Then the problem would pop up again. Took it to our mechanic who is an independent HD trained tech, with an outstanding reputation here on the Coast. He checked fuel tank internals and changed the filter. Checked for inlet manifold air leak, found one so replaced all seals. Cleaned IAC. Bike ran fine for a month, then started the same b.s..
Replaced IAC. No difference. I should mention that there were no DTC's thrown. Went through the process and changed out all inlet sensors as well as CPS. After this, bike ran good for almost a year. I should also mention that this is so intermittent, we've left it with him for a couple of weeks, where he's ridden it every day and it hasn't faulted!
Anyway, we had it in his shop for 5 weeks recently to have the front end powdercoated. Maree picked it up after completion, got 2km down the road and the ****in thing started doing it's farting stalling thing again. GOT IT restarted, straight back to the workshop, running like a dream. Hooked up to the SERT. Nothing out of the ordinary.. rode home, no further issues. Fast forward a couple of weeks, just doin a short local loop up a tight hilly road (1st and 2nd gear) starts fumbling a bit. Across the top then back into traffic in town. Thru a set of lights, missing, coughing and dies all together. On the ph, the tech comes out. This time it's thrown a code for ETS fault. We restart it after maybe 30mins with no probs. Back to the workshop and sensor replaced. All good we think. Have done maybe 400km since then with no probs. GOT out today rode for 25km at 80kph all good. Slow dow/stop for lights - idling at 1700rpm. ****. Next set of lights same deal. Next set running ok. Next set, wants to idle slow, bout 750rpm. Stop for fuel, a bit hesitant to restart. Carry on a bit further and end up in gridlock traffic. Stop n go ****. Bike missing farting etc. Dies all together. Restart by cranking throttle wide open. Get out of the traffic and on to the highway all ok. Get off to head for home thru a couple of T intersections. Missing wanting to die. Have to keep the revs up to keep it running. Get home, again after 15-20km of 80kph, bikes running perfect. I took it for a 30min run and tried to replicate all the **** we'd just been thru and it didnt miss a ****ing beat! Anyone got any ideas? The only sensor that hasn't been changed (I think) is the VSS, but there have been none of the other symptoms that go along with this, e.g. Speedo fluctuations, turn signals not cancelling.
I'm sorry this is so long and drawn out, but it's got us ****ed
Thanks for any thoughts!

 

I seriously doubt that the fix I had to do is anywhere near the problem you have, but, similar symptoms.

Last Friday, about 10 minutes after filling up, my bike started backfireing, sputtering, wanting to stall, the idle bouncing around between 800 and 1200 rpm's. The engine would want to die under hard throttle, and then grab.

I drained, and replaced the gas. It improved, but still doing the idle thing. Replaced the plugs, boom. back in business.

 

Thanks for the reply. This has been going on (and off) for 18 months. Numerous tanks of gas. At least 2 sets of plugs. Everybody is running out of ideas.

 

I had the same almost exactly, but on a older bike. It was the cam position sensor.

 

 

There is no IAC sensor in any Harley...Was it something else you are thinking of?

 

 

 

 

what you describe in the first post ...kinda sounds like a head temperature sensor could be acting up ....
this would cause the ecm to add warm up fuel when the motor is hot already ....making it too rich ..causing the low idle ...
or a loose connection at the sensor itself ...