'99 cel, cold start/idle problems

[MZ2215]

well it's gotten cold here in MI and a couple weeks ago my CEL came on. it's a 99 sohc with ~120k on the clock. since the light came on when i start it when it's cold it barely idles without me manually giving it throttle, and if it's cold enough dies. after it's warm it runs fine.

i'm a college student and live in an apt. so i'd like to have an idea of what i'm in for before i go home and take it somewhere or try to figure it out myself.

 

[MZ2215]

any ideas?

 

[Donner]

Lots of suggestions...

There are a lot of areas to look at, but I'm only going to add that you might get the fuel filter changed and use a good fuel, like one with techron (or a detergent) Oh well, Chevron. The other items are tech, I know nothing there... but how's the maintenance on your vehicle, mileage, servicing up to date?

 

[daffy]

3 things pop immediately into my head: (I'm assuming here it's a 4.0 SOHC)

lower intake seals, vacuum leak, and IAC. Search for the 3 of them, and see if your symptoms match the threads.

The IAC is easy, the o-rings, not so much. But they are cheap (relatively speaking).

Vacuum leaks can be a real PITA to find, there is a thread somewhere on here that is a checklist so to speak of how to troubleshoot them.

See if your X has had the 00M12 recall/TSB done (again, assuming it is a SOHC) (it has the newer o-rings). if not, that'd place it higher on my list. (as short a list as it is).

Good luck, and please report back if/when you get the problem fixed!

 

[rob17san]

I think it is the IAC. Easy enough to clean and or replace. Right under the cover marked "SOHC" Same problem I have had in 2003. i had to pay $250 to the dealer to figure it out, but the IAC valve is relatively cheap. I also recommend a fuel filter change, and BG 44K or seafoam in the tank.