Rough idle when cold?

[shadow11]

Since the temperatures have been getting colder I have noticed that in the morning when I first start the car and drive off that I have a rough idle. It is only rough for about the first five minutes or so and really isn't too bad unless I get stopped at a light in that first five minutes. If I get stopped within the first five minutes then the car seems like it is trying to jerk ahead slightly while I am sitting still. Once I get going then all is fine? Do I have a bad maf sensor?

[WarMachine7]

what oil do you run?

WAR MACHINE

[shadow11]

I haven't changed the oil yet since I bought the car. It was changed at the dealer when I bought it but i'm not sure what oil they used. It says full synthetic on the sticker they put on the windshield. That was 4k miles ago and I plan on changing the oil in 1,000 miles.

[laselvasurf]

Could be a lot of different things. I had the same problem and it was a vacuum leak from my intake manifold gasket. I also had a similar cold rough idle when my VCGs were leaking and causing oil to get onto the spark plugs. If I let the car sit for a couple days, it'd be rough for the first couple minutes if I let it down to idle.

Most likely though, it's a vacuum leak. You could check your maf sensor, if you have a code reader (to reset it after) just unplug the maf while it's running rough and see if it improves, or makes it worse or the same. If it's better, then your maf if bad, worse or the same, the problem lies elsewhere.

[WarMachine7]

Yea checking for vac leaks its a good bet, but get that oil changed and other maintenace done, so you can sleep better at night.

WAR MACHINE

[Airbrush It]

I had a similar problem, and replaced the intake manifold gaskets (PITA)
I also ended up replacing my MAF... between the 2 it solved the problem.. I'm thinking it was mainly the intake gaskets..

[IcemanBHE]

Def vacuum leak. 100%.

[kulgan]

I had exactly the same problem. Fortunatly for me when i checked for vacume leaks it was only the throttlebody gasket.
A new gasket and a couple of hours work and it's been running great ever since...