Running hot

[vombil]

Gday guys

I've encountered this a few times over the years. VS runs up red hot before fan comes on (like nearly cooked) then temp comes down but not to an acceptable level. Leaving the a/c on will avoid it running up to begin with.

It's had a coolant flush and thermostat replacement.

My thoughts are this is the early stages of a head gasket job. I've gutsed the thermostat in the past in other cars and it doesnt achieve much as the water flows faster and has less time to cool.

Keen to get some feedback ie change CTS or radiator or?? thanks

 

[Immortality]

Make sure both the low and high speed thermofan settings work.

 

[vombil]

Make sure both the low and high speed thermofan settings work.

ive swapped relays and then done the test with CTS diconnected and the low speed seems to work. Harder to hear if the highspeed kicks in but I'm pretty sure it does thanks

 

[Immortality]

How old is the water pump? If it's been replaced you only used 1 gasket?

Just a sanity check, V6 or V8?

 

[vombil]

How old is the water pump? If it's been replaced you only used 1 gasket?

Just a sanity check, V6 or V8?

I could do a pump whilst ive got thermostat housing off (checked thermo wasn't gutsed or backwards)

V6 mate

 

[vombil]

RESOLVED! As suspected along the way - the ECU was responsilbe for giving a high reading on guage. The engine isn't running hot at all. Hopefully this helps someone as it's probably the last thing anyone would consider to be the culprit

 

[NORTI]

thanks for the resolution. Most often people leave these threads hanging

 

[ephect]

RESOLVED! As suspected along the way - the ECU was responsilbe for giving a high reading on guage. The engine isn't running hot at all. Hopefully this helps someone as it's probably the last thing anyone would consider to be the culprit

Im curious about this as the gauge sender is separate to the ecu sender.
How did you actually resolve this?

 

[BlackVXGTS]

Im curious about this as the gauge sender is separate to the ecu sender.

Quite correct, perhaps the sender was replaced? Item below is from VS Commodore issues:

Temperature sender unit - The temperature sender unit used in VS V6's was carried over from VR's, but the location was changed to a hotter part of the engine. This may cause higher temperature readings on the gauge before the thermo fan cuts in. In mid 1997, the sender unit was revised to suit the new engine position and engine temperatures, which show a lower reading on the gauge before thermo fan activation.

 

[AmericanGuyInAUte]

Make sure both the low and high speed thermofan settings work.

Tell me more. DOes it have 2 thermostitches, two relays? My temp goes up about 3/4 of the way and then comes back down. Is that normal? To me it seems a little high. with the A/C on it stays halfway. Could my car have a similar problem?