Howdy all - this forum has always been a great source of information, so hoping one of you learned souls can assist me in diagnosing a problem I am having. Bike is a 2006 Road King Classic, 88 ci, 34,000 on the clock, EFI.

Problem is once the bike gets hot the idle is all over the place. Will climb gradually and check engine light goes on, then after a few minutes it may reduce back to near normal and check engine light goes off. Sometimes will drop to nothing and die at a light, but will restart immediately. Seems to be heat related for sure, as it only happens once the bike is warmed up and has been running for a while. I had this problem once before, and had a well reputed local shop look at it - they replaced the Idle Air Controller and it seemed to take care of it for a short while, but now the problem is back.

Anyone have any thoughts. From what I've been able to find and read the idle circuit just isn't that complex. Wondering if I just got a bad IAC ?

Thanks for any input...

 

You need to check the code for the check engine light. That will tell you what you have an issue with. You can do this yourself , I'm sure you can find the procedure with a search. More than likely IAC is bad or needs to be calibrated. Keep in mind IAC will try to compensate for other issues such as intake or exhaust leaks.

 

Take of your air cleaner. Inside the intake at the top there is a small hole. Spray some brake fluid in there to unclog. This is an O2 sensor that is clogged. Next use some seafoam in the gas. This will unclog anything else.

 

That is not an O2 sensor. It an Idle Air Control (IAC) valve. But yes this could very well be your problem.

 

Brake fluid? Really? Try some carb cleaner.

 

LOL - thanks for the input guys. Don't think I'll spray brake fluid in there, but I knew what you meant and appreciate the input. Good thought about checking the code. I don't think its storing one - the light comes on then goes off - doesn't stay on, but I'll check codes. Thinking either the IAC or the TPS is bad. They're cheap and while in there might as replace both, but going to check codes first....

Now where did I put that brake fluid