Cold Starting/Cold Running Problem

[ddenton749]

My 1993 Explorer has recently developed an aversion to cold weather. This morning it started on the first try and idled fine. Then, after about 2 minutes, I stepped on the gas it stalled. When I tried to start it again, it behaved like it wasn't getting fuel. (Cranked fine) After several tries it started and I had to hold the RPM's up around 2000 until the rough idle cleared up. Kind of reminds me of the old days when a carburator could flood an engine and you had to floor the gas pedal to clear it. Yesterday it was fine. A couple of mornings ago it was hesitating for the first few minutes of driving-like it was starving for fuel. The fuel filter is about 1 year old. Is there a cold start valve or a cold start sensor? If so, where do I find it/them?

 

[mikeh]

Search on IAC valve. You should find plenty of info. That's my first guess if it idles fine after it warms up. The quick test is to hit the air conditioner when it's in park and see if the RPM's jump to compensate. If the RPM's jump that means that your IAC is working and you might try other things like the MAF sensor.

Good Luck,
mikeh

 

[Alec]

Could also be the fuel pressure regulator going; but I do agree with the IAC suggestion.

 

[ddenton749]

Well, so far my Explorer has started fine. All it took was to clean the air by-pass valve (IAC). Thanks for all your help.