Trouble with cold start-up

[floydr007]

Hey everyone, i just searched this because i figured it was common, but i didnt see anything exactly like my problem. My 99 SOHC sport sits outside in a parking lot (im at school) for up to a week in between when I use it (its been anywhere from 20-40 degrees). I used to struggle getting it to start sometimes (Id have to hold the gas pedal like 1/2 throttle and hold the starter for a few seconds). Well i took it to a shop, and my throttle body was pretty dirty, so i had that cleaned because I thought it might be restricting airflow when the throttle is closed. All was well for a few weeks. Just last night, I went to start the car, and it started immediately, except it would not idle after i started it. I had to press the gas pedal to keep it at about 1000 RPM. i let off to see if it would just fix itself and it died. Also, when the rpm's would drop down real low, all my interior, and headlights would dim and almost turn off. I started it again and revved it to about 3500 or 4000 rpm, and it just settled right back at a perfect idle, and there were no problems for the rest of the night. Do you think my IAC is bad, or possibly an electrical system issue? By the way, I have a MAC intake, do you think that one breather might be leaking? Thanks for the help.
jonathan

 

[jp450]

Clean or replace the IAC.

 

[aldive]

I would suspect problems with the IAC.

I have tried to clean them and never had any luck, so I just replace the IAC when defective.

Good luck ....

 

[spta97]

I would suspect problems with the IAC.

I have tried to clean them and never had any luck, so I just replace the IAC when defective.

Good luck ....

Ditto. I got mine off of Rockauto.com for $65.98 shipped. On the V8 (mine) it is right on the top and took about two minutes to replace. I am not sure about the V6 though.

I tried to clean mine and I think it actually made it worse. If you want to test, unplug the connector to it and see if your engine fails. Also, take it to AutoZone and see if you are getting any codes. I got a bad IAC code (along with a check engine light) so I was positive that was my problem.

 

[floydr007]

Thanks for the quick replies, and one more question, is it normal that the lights were dying when the cars revs were going down before it stalled? is it just because the alternator wasnt spinning fast enouhg to be producing electricity? Thanks.

 

[spta97]

Thanks for the quick replies, and one more question, is it normal that the lights were dying when the cars revs were going down before it stalled? is it just because the alternator wasnt spinning fast enouhg to be producing electricity? Thanks.

I'm not sure about this. If your battery had enough juice it should keep the lights bright. If they faded it could be a bad battery or bad alternator. I would see what others have to say though.

 

[floydr007]

Im definitely thinking the same thing, but at the same time its kinda odd that it had enough juice to start the car w/o a problem.. Also, I ordered a IAC from rock auto today and should have it in tomorrow. Are these hard to install on the 4.0 SOHC, i have basically no tools out here at school. Im thinking im going to take it to a shop when i get it in, and hopefully this will solve the problem. Any input greatly appreciated

 

[jjay66]

IAC easy change!

Hi I'm not remotely mechanically minded and I took apart the IAC in 10 mins to clean it. Actually it solved my idling problem although I still need to rev her up for 30 secs from cold.
Thinking I might replace the IAC and see if there is a further improvement. Basically all you need is a socket set. Four screws hold the plastic cover in place and then two more release the IAC.

Follow this link for step by step + pretty pictures. Good luck.
http://www.explorer4x4.com/iac.htm