Erratic Heat
Erratic Heat
The GXP seems to warm up perfectly, but after about a half an hour of driving it will start to feel cool in the car. The engine temp guage reads normal and I usually have the auto climate set on manual at 90 degrees. It actually cycles from warm to cool and back to warm. I've never had it do this before. A couple of times the blower seemed to cut out and then back on. Any clues?
- dpnewfie
- Posts like an LN3

- Posts: 598
- Joined: Thu May 22, 2008 8:01 am
- Year and Trim: 2005 GXP
- Location: Conroe, Texas
Re: Erratic Heat
Its normal.
2012 CTS-V Coupe, 4k miles and counting.
2005 Bonneville GXP, 200k and SOLD!J Wikoff wrote:It has been an honor and privilage to have been serviced by you.
Re: Erratic Heat
I cant say if its normal as I havent had mine but a week. However I would check to make sure your coolant level is all the way full in the radiator.
Brian
Brian
- CMNTMXR57
- Certified Bonneville Nut

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Re: Erratic Heat
IF you are getting heat out of it when you want heat, then I'm thinking this is fine. Say if you set it at 80*, it's just adjusting automatically to maintain that 80*. One minute it may seem as though you're getting hot air, then a minute or two later, almost cold air by comparison.
The first thing I would check, is set it to 90* (the max) and verify that you get sustained hot air blowing out. IF this is not the case, three areas I would start looking at.
1) Thermostat first
2) the actuating mechanism on the blower housing that opens/closes airflow (typically how it regulates that auto air temp is by closing/opening a door)
3) Headunit.
The first thing I would check, is set it to 90* (the max) and verify that you get sustained hot air blowing out. IF this is not the case, three areas I would start looking at.
1) Thermostat first
2) the actuating mechanism on the blower housing that opens/closes airflow (typically how it regulates that auto air temp is by closing/opening a door)
3) Headunit.

Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*
Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
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