Hello all im new to the forms and hoping for some help. Ive got a 98 electra glide with fuel injection evo motor. The idle has been very erratic since i got it a few months ago. At first it would just idle up and down between 900 and 2000 rpms whenever it felt like it. I read alot of people on here saying to change the temp sensor. I did this and then the problem changed. Now on cold start it will idle up to 1,800 rpms for around 6 mins and then slowly drop down to 900 rpms. It will drive fine the rest of the time but when you started it up after sitting for about 10 mins it would do the same thing all over, i dont think the motor cooled down that fast. I then got out the manual and did the idle cold and hot relearns. Got the cold rpms to be about 1,500 which is what the book says is good. Seemed fine for awhile. Then i started it up again after a 10 min sit time and suddenly im way up to 2,000 rpms. I did the cold relearn again, but then i unplugged the battery to loose then idle memory and now the bike wont idle. just chuggs between 1,000 and 1,500 rpms. Im totally at a lost as to why it wont idle after battery reset. This isnt the first time ive rest the battery. Id be open to any advice, im about ready to tear my hair out and scrap this darn thing.

 

On your MM injection system you need to clean the air bleeds in the intake from time to time. Take breather cover off and look at the 10 and 2 positions in the intake and you'll see 2 small holes. I use carb cleaner or SeaFoam to clean them out when i have an idle problem and it helps. If not that try to have the IAC motor on your throttle looked at, not sure what the reading should be, but that could be part of your problem.

 

I have cleaned the air bleeds previous to this new issue. It seems possiable the IAC is bad but I can see it moving and when the bike is at warm idle it is all the way in where it should be. The odd thing now is after it is warm it is chugging and won't maintain a smooth idle and this only happened after a cold idle learn and battery power removed. I'm very worried I messed up something expensive like the motor

 

You haven't hurt any thing, it just needs to be re-adjusted. Here is a method that requires no diagnostic tools. This is from an HD tech.

By Patrick Zambori,

This describes a method to set cold and hot idle speed on Magneti-Morelli EFI systems.

First, when it comes to setting cold idle, the service manual leads you down a path of frustration. I have a very simple and effective way of adjusting it. If you start the engine stone cold and it idles below 1200 rpm (after it stabilizes) then turn the cold idle screw (in linkage, on the side that rotates with the throttle plates) in. If it's over 1300 rpm, then turn the screw out (therefore, set cold idle speed at 1200 rpm for TC-88's). It's that easy . Also, to guarantee that the idle will be recognized by the ECM, I run the bike until it's fully warmed up, turn the hot idle (in the throttle body, forward of the front intake, near the bottom) up to 1200 rpm, shut off the ignition and pull the 5 amp fuse (in the fuse holder on the ECM brackett), run a lead from the cold (relay) side of the 5 amp socket to ground. Let it sit for 15 minutes or longer if practical, then put the fuse back in and warm it back up, turn it back down to 1000. Works like a charm.


If you need voltage readings you can get them by back probing the gray/violet wire at the TPS. Try the above before you reset the TPS.

Always pull the two fuses under the right side cover to allow the ecm to re-learn the new idle position, otherwise it will go back to previous learned position. After you replace the fuses, switch on an off two times and allow enough time for the idle control to complete all of its steps.

 

Ok this is we're I'm at now. Got the hot idle set no problem. Once it warms up it is fine the rest of the time. I can't get my cold idle settings to stick. I set it and every start up the idle slowly creeps up. I was at 1200 rpm and a week of on off riding now I'm at 1800. I was also noticing that the hot idle restart idles higher then an ice cold start. How long should the idle stay up after a cold start anyhow? Mine is idling high for 7 to 10 mins even if it's warm outside that seems too long to me. Hot restart I get high idle for 3 to 5 mins, and that's after only sitting for 10 mins! I'm about fed up with this stupid system, thinking about installing a carb. Wonder if that brand new Harley temp sensor I got is faulty.