mtman

My wifes' 94 SC400 has a fluctuating idle once the engine temp has come up as indicated on the h2o temp gage. It idles great up until that point and accelerates to 60+ quickly with no hesitation. I've cleaned the IACV thoroughly but doesn't seem to help. I know somewhere in this forum is the answer. Have thought it could be an open circuit in the IACV motor once it gets hot or fuel pump ECU and/or the O2 sensor. Any help would be appreciated.