Idling Probelms

[Nealeis]

88 camaro 2.8 Mutiport 5 spd
he's the problem
start the car runs fine for about 5-20 mins then the idle kicks up to 2000-2500 and won't kick down replaced the TPS and the EGR and still having the problem just can't seem to figure out why this is doing this i've been thinking ECM but don't really want to waste $180 on a new ECM and not have it solve the problem if you guys have any idea's or fix for this problem thanks

[WS6 VERT]

Any codes stored? When it idles high, try spraying all around the intake ports w/ carb cleaner to look for vacuum leaks.

Could be tons of things, on top of the ECM, like a bad IAC valve, etc...

[Nealeis]

IAC has been checked no fault no vac leaks checked all Replaced EGR And Tps if you shut off the car and restart it the idle corrects but again 5-20 min kicks back up to 2000-2500 rpm

[WS6 VERT]

Try giving the ECM a good whack and see if the idle fluctuates. If it does, then sure enough, the ECM is bad.

[Johnny G]

Originally posted by DenaliTech:
Try giving the ECM a good whack and see if the idle fluctuates. If it does, then sure enough, the ECM is bad.:D
Now there's an excuse to buy a new one.

[Nealeis]

question is it a bad thing if the ECM is hot to the touch ????

[LL6]

I've never noted my ECM as hot when changing out chips.

[WS6 VERT]

Yes, they do get hot... Not so hot that it burns the skin, but very warm...

[Nealeis]

Well i went to whack the ECM like ppl where telling me to try to see if the ECM was faulty and man you could fry a egg on it note after the car was only running like 20 mins

guessing that it should not be that hot at all since computer really don't run well under heated condtions
so question is does this mean that the ECM is somewhat toast ?

[Nealeis]

thanks disregard other post !

[Nealeis]

Well i removed the ECM form it's mount whacked it idling didn't do anything but now with the ecm not mounted the car wants to stall and the high idling still happens but didn't have the stalling problem till the ECM was moved i check all the wires and they are fine
Any ideas ?

[WS6 VERT]

Is it stalling because its out of the mount or becuase you whacked it? If you have a poor solder joint or otherwise faulty connection somewhere in the ECM, it is usually agitated by heat and/or vibration. Sounds like its mostly heat related, untill you induced some "manual vibration" (aka whacking it). Unfortunatly, these "brain boxes" are like voodoo, and sometimes it takes an educated guess to diagnose one. And with "guesses", educated or not, there is always the chance that its not the problem :(

[Pantera61]

I was having pretty close to the same problem. I did purchase a new computer from the local GM house, but that is $280 that I wasn't sure about. It did fix the problem though!! Try bending the wires as if it was mounted, there might be a small short and was working when mounted. Just a stupid question to see if it might help, is the tb shutting all of the way?

[Hairbear]

On TPI cars if the coolant sensor is faulty and giving a cooler reading it will cause the idle to be high,so I guessing multiport would be the same. Also clean the IAC with carb cleaner but make sure it doesn't run down into it just clean the spring and pindle.
I got a ECM out of a junkyard for $55 recently and most junkyards will backup what they sell as being in working order.