Every time I start the car up and tap the gas the RPM goes up and than falls down to 2nd line and than up to 10 and down to 4 up to 10 down to 8 and than stabilizes, the engine sounds like it is about to shut off. However, when I drive the car for a few minutes after it warms up, the RPM is ok, no matter how much I rev it.Any ideas what the prob. is? Nothing too serious, but i want to avoid big future problems by fixing small ones. Thanks ahead, this forum is awesome.

 

Most likely a faulty idle stabilizer valve. Located under the intake.