What's happenin guys! I am have a strange idle issue that started about a week ago. When I start the truck in the morning the truck idles a little rough for about 10 seconds right after start up and then it idles perfectly. What is weird is that it runs perfectly until I pull up to this one particular light (that I always catch on red) on my way into work. At first I thought it was because this particular stop light is on a very steep incline. Anyways, the idle bounces from 800-1200 and feels like the engine is cutting off when the idle falls. Soon as I pull off from the light she runs perfectly the rest of time. My theory was further supported the other day when I went a different way into work and she ran perfectly.

However, now I think the light is just a sheer coincidence. I believe the issue is distance related. The last two days home from work the same issue happened and the approx. same distance as in the morning. If I had to guess I would say the distance is about a mile and a half. After it happens I can run the truck the rest of the day and not have a single issue. I have never had a problem with either of my 22re(s) and I am anal as ˟˟˟˟ when it come to maintaining my girl. So I would like to take care of this now.

I have searched but I havent found anyone who was having an issue like this. I don't think it's a vacuum issue and the idle is set properly. I was thinking TPS perhaps, but others I found who needed to replace it were experiencing different symptoms. Anyone have any suggestions?


Thanks guys

 

If the issue disappears if you take your foot off the brake pedal, this sounds like the classic 'idle surge' effect that comes from having the idle speed set just a touch too high. The EFI always cuts gas delivery when the brake pedal is pressed; When the idle is set past a certain RPM, and you press the brake, you get the effect.
Another often overlooked cause of a slightly too rough idle can be age-shrunken rubber seals on the oil dipstick. Remedy: New stick.

 

Thanks Keith. You might be dead on. The issue only happened for about 60 seconds today and when I took my foot off the brake the idle went back to normal. It's strange that it only does it for such a short time. I will adjust the idle and will report back.

I did find out that my 4 year old radiator has a hole near the radiator cap. Nearly overheated today. Looks like its time install another one.

 

Your idle is to high or your TPS is not set up right. This will cause a bouncing idle as the CPU starts to hit fuel shut off.

 

I haven't touched it yet because everything has been fine since I mentioned anything. Since I have to get a new radiator I decided to order a whole bunch of parts. I thought while I am in there I might as well get some **** done. Will do a tune up, valve job, replace all the vacuum lines and all hoses. This should take care of everything.

 

Well the problem has now come back in full force. The truck is having a rough idle when it started up in the morning. I only lasts about 10 seconds, but it seems to be getting worse. The Idle surging has also returned (again only for a short time, then it goes away). I am starting to think it is a TPS issue now. With the AC off the truck idles low (around 500 rpm) and when I to adjust the idle I almost had to back the adjustment screw all the way out before I noticed any difference. Just curious what would cause the TPS to be off all of a sudden?