Car idles lumpy at startup..

[TType84]

a few days ago my car began idling like **** only at startup.. ill start it and it'll lope like i have a huge cam.. or like its running on 3 cylinders. after about 5-10 seconds it'll clear up on its own, or if i tap the gas, itll clear up

needless to say it ONLY does it right after the car has been started...

any ideas what could be causing this?

 

[justabuickv6]

Mine does this too but only about once a month. Run extremely rough for about 10 seconds.

Clean plugs and tuned properly. Strange!

 

[AirBuick]

Check to make sure you're water level is not going down. If the HG is leaking water into the combustion chamber, then it will run rough until it burns all the water out of the cylinder.

 

[justabuickv6]

AirBuick. Thanks for the info. No leak here.

 

[GrndNatnl]

In cooler weather, on a cold start in the morning, mine sounds like it misses a little when it fast idles for about 30 seconds or so. I figure it might be cold plugs or something maybe?

 

[TurboJim]

Doles your fuel pressure drop in the time it sits before the start? Possibly a leaky injector or 2

Jim

 

[justabuickv6]

Good point TurboJim. My FP goes to zero after a couple of hours.