Car gets hot with ac lever on cold?

[pontiacgp]

I am repeating my question but it seems you missed it the 1st time...

"Where do you have the temperature sensor located? Do you have a laser temperature gun to verify the coolant temperature as you change from heat to a/c and visa versa? "

 

[pagrunt]

After reading your other post about overheating I'm going put my money on the fact the rad was low from the leaking thermostat housing. I think it's safe to say you never checked/kept up on the coolant levels. Fix the leak, replace what you said you're going to, top off, get everything up to operating temp, then you should be back to normal. While you're at it check all possible leak spots in the system.

 

[Clone TIE Pilot]

Wasn't you vacuum switch broken?? What did you do to fix it? Maybe something with that has to do with it?

Vacuum leaks will make a engine run hot, even with a healthy cooling system.

 

[Blake442]

Sometimes aftermarket temp senders do not extend far enough down into the coolant jacket as necessary to submerge themselves in coolant without special fittings.
With the sender in your intake next to the thermostat housing and the heat off, the coolant builds within the intake like it should until released by the thermostat into the radiator.
But if your coolant level is low, when you open your heater valve, the extra amount of fluid leaving the engine to circulate thru the heater core can leave your temp sender exposed and read as a hot or cold spot.

Fix your leaks, fill your cooling system and reservoir, and buy a temp gun to confirm the actual temps.

 

[MrSony]

I am repeating my question but it seems you missed it the 1st time...

"Where do you have the temperature sensor located? Do you have a laser temperature gun to verify the coolant temperature as you change from heat to a/c and visa versa? "

And I will repeat my answer. Its in the intake manifold near the thermostat housing. The only place for it. I do not have a temp gun. What would I point it at if I had one? Hose? Rad?

 

[TURNA]

To double check if the gauge is working properly

Harbor freight sells a decent one for 15 buxx plus you can use the 20% off coupon and the free gift coupon!!

 

[MrSony]

There are no vacuum leaks. Engine has a steady 15-17" of vacuum at idle with 10* timing and a 276/281 adv. duration cam.
Its done this for a while, the swinging temp readings. It ONLY ever does it when The car is running and I have the temp lever on cold. If its on hot its fine. I can make it do it everytime. Its not random. Its done it since I had this engine in the car. I didnt have a functioning heater system with my other engine so I never had reason to mess with theheat or its controls.

 

[MrSony]

It does it moving down the road and at idle in my driveway.

 

[pontiacgp]

And I will repeat my answer. Its in the intake manifold near the thermostat housing. The only place for it. I do not have a temp gun. What would I point it at if I had one? Hose? Rad?

since you have it near the thermostat I would check the temperature of the thermostat housing and have someone else control the heat and a/c so you can check to see is the temp is dropping identical to what the gauge is reading. A laser temperature gun is useful for other things, like checking the temperature of the in and out of the catalytic converter to see if it's good and if you have headers and develop a miss it will help you find the cylinder which is cooler than the others by taking a reading on the header tube.

 

[TURNA]

Well its winter so at least you have heat!!!