Heat Temp Fluctuation

Plimbob · Dec 16, 2018

The heat temp in my 07 Tahoe is fluctuating. I have it set at 84 and it will blow warm for 10 minutes then the air output will get cooler for a few minutes and then return to warmer. I re-calibrated the blend doors but didn't help much that I can tell.

I assume its a blend door motor issue but how do you tell which motor? I think there are three?

Any thoughts or experience with this would be greatly appreciated. Its getting pretty chilly are here and only going to get worse!

Thanks,
Tim

Doubeleive · Dec 16, 2018

you need a tech2 hooked up so you can see what the temp sensors are reading, if there is a faulty temp sensor it could be causing the problem, I would think a blend door would just simply not work or it would just stay hot or cold not go back and forth on it's own, if you have a scanner capable of reading the body codes there may be a open code or stored one, that type of code would not make the check engine light come on..

Plimbob · Dec 16, 2018

Wes,

I don't have a unit capable of reading body codes. I'll have to check around with friends and see if anyone has one.

As usual, thanks for the insight much appreciated.

Tim

Doubeleive · Dec 17, 2018

if you have the spare money it can be worthwhile to pickup a tech2 clone they run around $300 +/- on ebay, eventually it will pay for it's self over time, I have 2 gm vehicles and kind of a 3rd and I bought mine a few months back I think I have broke even on it already just doing different things it sure can come in handy for things like this

Plimbob · Jan 7, 2019

Hey Wes,

Circling back on this. If there was a temp sensor would the engine still be operating at normal temp?

I was unable to find anyone with a Tech2, look like I will need to purchase one.

Thanks,
Tim

Doubeleive · Jan 7, 2019

Plimbob said:
Hey Wes,

Circling back on this. If there was a temp sensor would the engine still be operating at normal temp?

I was unable to find anyone with a Tech2, look like I will need to purchase one.

Thanks,
Tim

the HVAC temp sensors would not affect the engine temperature in any manner if that is what you are asking, they are completely separate from each other.

Plimbob · Jan 7, 2019

Wes, thanks for the clarification.

Heat Temp Fluctuation

Plimbob

Full Access Member

Doubeleive

Wes

Plimbob

Full Access Member

Doubeleive

Wes

Plimbob

Full Access Member

Doubeleive

Wes

Plimbob

Full Access Member

Similar threads

Forum statistics

Latest posts