snagitseven

After sitting in the garage overnight, I started the ignition in my 2001 2.7T and the engine ran rough, missed and sputtered for about a minute or two. This started only recently and doesn't happen with each cold start up - it has happened only twice over two weeks. No problems after the first couple of minutes or subsequent starts.
I have about 5000 miles on the car and haved filled up at the same Conoco gas station since the first time it happened (I've used their gas since the car was new with no problems). I know I'll bring it in to the dealer and it won't do it. Any ideas?

DWC_2.7T

A little bit of rough idle is normal for a cold 2.7T, but nothing severe or strong. Just a guess, but I believe it takes a minute for the oil pressure to stabilize in the auto-adjust cam timing circuit. How often do you give it some good exercise...a good distance drive at higher speed? I suggest a bottle of Techron in the gas every 3000 miles or so too.

Richard Solomon

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2.7tDallas

When the gauge went back to the left all the way, the engine would idle rough.

Of course mine only stopped working after the engine warmed up.

It does follow however, that if the engine computer thinks the engine temp is something different than what it really is, then the gas/air mix it produces could be wrong for the actual temp of the engine, and it could run badly.

captainbilly

Those are all season tires and the weather was pretty hot the last few months. The vapor pressure of the tires gets very high and when the car sits in the garage the vapors get into the intake and in combination with the CONOCO gas you get the missing. That's why the car runs well after warmup, the tire vapors are now gone.

Sorry about the silly story but I didn't sleep well last night. It is however a good example of bad scientific method. All of the above explaination could be true, just like it could be true that aliens were responsible for the WTC coming down, but without some experimentation I would have no idea.

This seems to be a fairly common problem on 2.7ts. Mine also misses some times but the car always seems to drive just fine, other than an occasionaly noticable power loss which I am pretty sure is caused by sunspots mixed with radioactive particles left in space from high altitude nuclear tests.

snagitseven

the engine misses badly for a couple of minutes - it chokes out after the gas pedal is depressed and almost stalls. Then all is fine. I drive about 25 miles on the Interstate both ways each day during the week. It gets plenty of exersize. I think I'll have the dealer start with the coolent temp sensor first - that seems to be the consensus here.