I have a 90 3.0l V6 4wd. Lately I have had to play with my idle adj. screw for the following reason.... When it is hot, like 90* + or so the idle is around 500 or lower. When the temp is around 80* it runs right around 800-1000. When the temp is 60-70* the idle is around 1300 or more RPM. Then when the rpm is around 1300 and I use the brake the rpm's on the tach seem to jump up and down from about 500 to 1500, in a quickly rising and falling motion. Does this make sense????

The mass air sensor has been replaced, but it has had this problem with the old and new mass air sensor. Maybe someone can help me out. Thanks in Advance

Nik

temp sensor bad giving the computer the wrong temp on the motor. probably kicking the fast idle circut in