When I first start my car and the engine is cold it seems to be misfiring for the first minute or two then it smooths out. Any idea what would cause this?

 

ECT.

 

My temp gauge is showing the right temps so how would this affect the running for the first 1 or 2 minutes? I don't mind changing it but I am trying to understand how it would affect the running.

 

temp sensors send a signal to the ECU which adjusts the mixture for cold start/warm start or "in between". For dead cold starts the injectors go very rich (in fact on older K-Jets there was a an extra "cold start injector" to enrich). If the ECT sensor is a bit off, its just enough to tell the car its luke warm (think along the lines of an old school manual choke - you start full choke when cold, half choke when luke warm and no choke when warm...). Once the engine fires up and starts preheating the cylinders and level sets its mixture, you turn the choke off - similarly for the car the enrichment ends after a minute or so because the car doesn't need it... So to your problem, its going to be one of two things - the temp sensor (common failure is to send an incorrect reading vs open circuit or short) or the idle control valve (which can get gummed up with oil/sludge from the PCV/intake - simple fix is to clean with MAF cleaner spray...)

 

Thanks mt6127, that's what I needed and thanks Robert for the video. I change that out and report what happens.