joetemp75

my z31 runs real rough when its cold the check engine light comes on when i drive untill it gets to warm temp. then when it is warm it purrs like a kitten. could it be a throdle pos sensor or do you guys have any suggestions before i sell my house to try to figure it out

MaxQ

Run the codes on the ECU. That's the first place to start.

craZed

Cylinder Head Temperature Sensor

madness

Air Regulator it should be open when its cold and closes when it warms up. so if it never opens you get bad running cold good running hot.