Rough Idleing When It Is Cold

[nbimports]

Hello,

I have 98 Explorer XLT with 4.0 SOHC engine.It runs rough for 1-2 minutes when it is cold and sometimes idle is so low it dies, afterwards runs fine.
Few days ago the check engine light went on and the code was for lean runnig.I cleared the code with scanner but this morning came on again.
Can somebody tell me what the possible problems are?

Thank You

 

[old mechanic]

The only difference that I know of between a cold start and a warm start is the air mixture.

 

[NHale623]

You probably have a vacuum leak, either the upper or lower intake manifold gaskets.

 

[floydr007]

You probably have a vacuum leak, either the upper or lower intake manifold gaskets.

I second that. I had the exact same problems and had the OOM12 recall done (I had to pay for it since I'm over the 72k mile limit). Its been running like new since.

 

[MONMIX]

there is / was a recall on the intake manafold O ring gaskets. When they get the funk this is how the truck acts.

 

[gijoecam]

ditto on the 00M12 gaskets. I'm having the same problem myself currently. Everything I've read points in that direction.

Good luck!

-Joe

 

[nbimports]

Rough Idling When It Is Cold

:thumbdwn: I UNPLUG THE MASS AIR FLOW SENSOR WHEN IT IS COLD IT RAN PRETTY GOOD NO STALLING SO I FIGURED OUT THAT MASS SENSOR COULD BE BAD.I SWITCHED IT WITH MY FRIEND'S EXPLORER BUT WHEN IT WAS COLD IT DID THE SAME THING AND HIS TRUCK RAN JUST FINE.I RED ON THIS FORUM THAT OOM12 GASKET COULD BE THE REASON.CAN SOMEBODY TELL ME WHAT IS THAT MEAN AND WHERE IS THAT LOCATED?

THANK YOU

 

[rmcknight]

The O rings in that recall are on the bottom of the lower air intake manifold - the one that connects directly to both heads. To get to it, remove the snow cover, + upper air manifold (including all the vacuum crap), then remove the lower manifold. It is said that you can oil up the o seals and screw it back on to fix the issue.