Won't Idle..... Wait..... Now it does??? What the heck!!!
09-03-2011, 02:08 PM
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Won't Idle..... Wait..... Now it does??? What the heck!!!
Girlfriend called the other day. Had drove my truck to work. Said when she started it, it wouldn't idle. So I went to look at it and sure enough it wouldn't in fact it almost didn't want to start. If you gave it a little throttle it would start and off idle it would seem to run fine. I was able to keep it running and get it on my car trailer to bring home. During this time it did start idling but only at about 400 RPM and sounded like it was about to die.
Now heres a quick rundown of past history. About a year ago my engine light came on. Had it checked... MAF sensor.... Tried cleaning it first but after resetting light it just came back on. Cleaned it again just for good measure but never went back to have light reset. Seemed to run fine and fuel mileage was same as before. So I left it alone. A week ago I had a heater core leak so i got to have some fun tearing the dash out of my truck.... thank god for some online instructions that made it really easy. After I got done with that I had the battery unhooked all day and the engine light was off. The girlfriend drove the truck all week with no issues and the light never came on. Then the above happened and i towed it home. Now I had it in my shop and was looking over things trying to find whatever... loose wires under hood, Checked all wiring I had unhooked when working on heater core but found nothing. I had a rough idle issue once that was the EGR valve or something and it had a bad hose. Checked it and its fine. So I stood there scratching my head....... I had started it and had it idling but really slow like it did when i put it on the trailer... So I walked outside to do something and left it Idling hoping it would throw a code or something. All of the sudden the engine revved up....
and idled back down low then suddenly the idle went to normal. Now it seems to be idling fine.
Shut it off and restarted... everything is fine. Now i did notice that the temp gauge had come up a little at this point. So maybe engine temp has something to do with it. I am currently waiting to let it cool down and I am going to try again to see what happens...............Any Ideas?????
Now heres a quick rundown of past history. About a year ago my engine light came on. Had it checked... MAF sensor.... Tried cleaning it first but after resetting light it just came back on. Cleaned it again just for good measure but never went back to have light reset. Seemed to run fine and fuel mileage was same as before. So I left it alone. A week ago I had a heater core leak so i got to have some fun tearing the dash out of my truck.... thank god for some online instructions that made it really easy. After I got done with that I had the battery unhooked all day and the engine light was off. The girlfriend drove the truck all week with no issues and the light never came on. Then the above happened and i towed it home. Now I had it in my shop and was looking over things trying to find whatever... loose wires under hood, Checked all wiring I had unhooked when working on heater core but found nothing. I had a rough idle issue once that was the EGR valve or something and it had a bad hose. Checked it and its fine. So I stood there scratching my head....... I had started it and had it idling but really slow like it did when i put it on the trailer... So I walked outside to do something and left it Idling hoping it would throw a code or something. All of the sudden the engine revved up....
and idled back down low then suddenly the idle went to normal. Now it seems to be idling fine. Shut it off and restarted... everything is fine. Now i did notice that the temp gauge had come up a little at this point. So maybe engine temp has something to do with it. I am currently waiting to let it cool down and I am going to try again to see what happens...............Any Ideas?????
09-03-2011, 06:48 PM
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IAC playing games:
The IAC (Idle Air Controller) may be getting sticky. Pull it off and give it a good cleaning, saturate the innards with WD40 and blow it out with compressed air, then dab a bit of silicon grease on the neoprene seal that surrounds the drive shaft.Another possibility is a worn TPS....Throttle Position Sensor.