Cold Start/Stumbling

[Davemc]

I'm new to this group and have a couple of questions. I have a 1993 Explorer Sport with 185k miles. It starts and runs flawlessly when the outside temperature is 80+. When the block is cold and the air temp is below 80 degrees it does not start on the first attempt. It will crank on the second attempt and it will stumble at idle for a few second and then run up to about 1200-1500 rpm. Any clues? A idle speed sensor perhaps?

Second question, the ABS light has begun to tom on when sitting in traffic after 45 sec-1 min. of brake application while sitting. The light resets after restart. Any help?

Thanks.

Dave

 

[TPLYNCH]

Could be the IAC, but that usually causes problems no matter what temp when it goes bad. Does the engine idle normally when you have the A/C on? Does it start normally above 80 if you start w/ the A/C on and off? If so, chances are not IAC. There is an Air Temp Sensor I believe. It has been mentioned on occasion in the forums. Not sure if that would cause your trouble if it were bad. Try searching for that, or AIT or ATI (I think I've seen it listed by those initials)

Welcome to the site, and good luck.

 

[Davemc]

Tom,

Thanks for the reply. The problem seems to persist whether you have the A/C on at start up or not. It only lasts until the truck has run for a few seconds and then after warm up, it will crank up just fine or if the ambient air temp if above 80-85 degrees.

It acts like a temperature related switch for enrichment is open. Older Bosch FI systems have a thermotime switch that activates a cold start injection function below about 90F. I wonder if this is a similar situation.

I'll look for the thread on the air temp sensor.

Thanks again.

Dave

 

[Josh]

I too have this problem! I just replaced the IAC valve and no change. I am at a loss. The Ford dealership told me the same thing. If you figure it out please let me know and I will do the same. ---------- Josh

 

[mikeh]

Sounds like a vacume leak somewhere possibly. Could be MAF cleaning needed. Could be new plugs and wires. The list goes on and on. These are just ideas.

mikeh