Cold weather start and idle

[spikolli]

1997 XLT 4.0 XLT 119 000km

I seem to be having trouble with startup in cold weather. (cold being -20 c and colder.) When the engine catches it will sometimes rev up to ~1000 rpm then stall out. If I carefully time a foot on the pedal I can keep it running for a few mins until it seems to rev up. If I take my foot off the pedal at this point it ildes fine at 1500 for a normal warmup cycle. Sometimes If I have a foot on the pedal I may need to run for 5 mins or so until warm enough. once warm it's fine. If I plug in the block heater it's better but below -20 not plugged in a total crap shoot.

here are my thoughts:

1. Cleaned IAC, no change
2. New Plugs and wires, no change.
3. Reading posts seems like intake manifold gasket leak.

Does this seem reasonable? an intake gasket losing seal in the cold allowing air past the MAF resulting in too lean= low rev=stalling? gas pedal= rich=warm engine =gasket seal. above freezing no problem at all.

Any and all suggestions welcome. I don't have a code reader but I'm not getting any check engine either.

Craig Spakowski

 

[Turdle]

1997 XLT 4.0 XLT 119 000km

I seem to be having trouble with startup in cold weather. (cold being -20 c and colder.) When the engine catches it will sometimes rev up to ~1000 rpm then stall out. If I carefully time a foot on the pedal I can keep it running for a few mins until it seems to rev up. If I take my foot off the pedal at this point it ildes fine at 1500 for a normal warmup cycle. Sometimes If I have a foot on the pedal I may need to run for 5 mins or so until warm enough. once warm it's fine. If I plug in the block heater it's better but below -20 not plugged in a total crap shoot.

here are my thoughts:

1. Cleaned IAC, no change
2. New Plugs and wires, no change.
3. Reading posts seems like intake manifold gasket leak.

Does this seem reasonable? an intake gasket losing seal in the cold allowing air past the MAF resulting in too lean= low rev=stalling? gas pedal= rich=warm engine =gasket seal. above freezing no problem at all.

Any and all suggestions welcome. I don't have a code reader but I'm not getting any check engine either.

Craig Spakowski

Hi Craig-
Welcome aboard--I see you have searched a few things on your own--

I think you are on the right track with the intake gaskets--in fact I'll bet on it.

 

[spikolli]

Do you suggest just upper intake gasket or upper and lower?

Craig

 

[bam_bam1ca]

The air intake temperature sensor and the temperature sensor for the ECM are both a whole lot easier and cheaper to try first.

Even if it was an intake gasket, I would think that it would still throw a code or two. You should get the diagnostic port read to be sure that the CEL isn't burnt out.

 

[BONJOVI]

So were you able to fix the idling problem in the end? If so how?

Any info would be greatly appreciated since i am having a very similair problem, thanx

 

[spikolli]

not cold enough for it to act up. When it gets colder I'm gonna kick at it again. I talked to a local wrench and he figured to check the coolant temp sensor to see if it is reading too warm.

 

[mawrazen]

Check for a vacuum leak.

 

[BONJOVI]

much warmer weather

Does anyone know if it is likely or possible that the gasket leak could cause the same problem in temperature of 48 degree F and below (10 degrees C and below) ?

Because thats what my explorer is doing, but obviously it doesn't take much cold weather at all to start mine acting up....

 

[Roger84]

Spikolli I just installed the upper and lower intake gaskets on my 98 SHOC. I had almost the exact same problem, with no codes. ( http://www.explorerforum.com/forums/showthread.php?t=193625 ) I fooled around with all the sensors and stuff but none of it helped. But the gaskets did the trick. I picked up the gaskets from ford dealer for about $25or so for upper and lowers. It took me about 3 hours to do the operation. I found on here somewhere directions with diagrams on the procedure that were very helpful. Not that you can’t do it with out them. When I inspected my existing lower gaskets they were definitely leaking.

You asked weather to do upper or lowers. my answer is to do both. the lowers are only 12 bolts from the uppers.

Bonjovi
my explorer would do this in 70 to 65 degree weather.

 

[BONJOVI]

I just did the lower intake manifold gasket and it solved the problem, idles great now

thanx for all the posts

 

[bkuhnke]

I have the same exact problem rough idle at start up, I am going to change out the gaskets this weekend. But I also have another question, assuming this thread isn,t dead.
I don't know to explain it very well so here goes. I will be driving and the engine will buck, it feels almost like the drive wheels are slipping and catching again. Seems to happen when it's raining or snowing. Could this be caused by the leaking intake gaskets or could it be something else.

 

[ThePhoenix]

sounds vacuum related...but I am not professional