car over heating when cel comes on

[sydrew]

i need help on why is my car is over heating when my cel comes on i pull the code the old fashion way and the multi meter needle just keep on sweeping saying it a code 1 but i drive it for awhile and the cel well go off and everything back to normal and i change a new thermostat too so well a faulty ecu make my car over heat thnx for looking

 

hmmm your situation is kind of similar to mine. although my car is only overheating cause the cooling fan decided to take a dump. my CEL comes on while holding RPM's up (during SMOG). i think mine is due to misfire. the CEL goes away after a few minutes of driving.

is your radiator cooling fan working properly?
waterpump?

 

[sydrew]

i didnt check on that yet but did u figure yours out yet if u did let me kno wat u did for your symtom thnx man

 

[fivestardsm]

Are you doing a key on engine off test, or a key on engine running test. If you aren't doing a test while you have the check engine light,(i.e. engine running) you need to.

 

[Hertz]

Quoting sydrew:
i need help on why is my car is over heating when my cel comes on i pull the code the old fashion way and the multi meter needle just keep on sweeping saying it a code 1 but i drive it for awhile and the cel well go off and everything back to normal and i change a new thermostat too so well a faulty ecu make my car over heat thnx for looking



The ECU cannot cause an overheating condition. The check engine light is probably coming on because of something, not causing it. The cooling system is mostly mechanical, with the exception of the cooling fans.