1995 3.4 auto. I have a very rough idle at cold start. It will usually correct itself after about 1 minute of driving. There are no codes in closed loop. I replaced the temp sensor, didn't help. When the engine get to normal operating temp it runs great. The MPG's are still the same. What am I not seeing? This just happened out of the blue. It happens no matter what the outside temp is.
Thanks.

 

how do your plugs and wires look like, are they old ? what about your o2 sensors ?

 

Plugs & wires replaced about 10,000 miles ago, O2 sensors about 1,000 miles ago.

 

what is your definition of cold? is this a winter-only problem, or just any time the car hasnt been running for awhile?

 

Cold, as in not started for several hours. Yesterday was cold in Dallas, about 45F[8D]