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Ask GM Tech (Cam) Your Own Question
GM Tech (Cam)
GM Tech (Cam), GMC Mechanic
Category: GM
Satisfied Customers: 29534
Experience:  GM Grand Master Technician 2007. 14 years experience.
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2004 GMC Envoy: problem im..start in the cold weather

Customer Question

Hi. I have a 2004 GMC Envoy. The problem I'm having is it will not start in the cold weather. It will turn over but the engine won't. Sometimes if I try long enough it will but the battery runs low. I had a friend use their diagnostic tool and the code PO651 Therm Code kept coming up. Not sure what it means, but it the summer it tends to run hot with high AC. Thanks and hope you can enlighten!
Submitted: 6 years ago.
Category: GM
Expert:  GM Tech (Cam) replied 6 years ago.

Hello, I'm Cam. Please include all the details about your issue so I can accurately advise you. I cannot see your vehicle so please be detailed.


By Turn over, you mean start, but the starter is still operating?



Customer: replied 6 years ago.
That's correct. The starter still works.
Expert:  GM Tech (Cam) replied 6 years ago.
Ok, that code is for a throttle reference voltage. Lets try a reset.
Take the battery cables off the battery, hold the ends together for 10 seconds then attach them to the battery and see what happens. This will reset the whole vehicle.
Customer: replied 6 years ago.
We have already reset the computer by doing that. It didn't take care of the problem. The code is actually Therm...I forgot the R, but don't know if that makes a difference.
Expert:  GM Tech (Cam) replied 6 years ago.
Ok, start by checking the wiring at the throttle body assembly and clean it out.
If you find nothing then you may need a new throttle body. THey are common on these to fail.
GM Tech (Cam) and 2 other GM Specialists are ready to help you
Customer: replied 6 years ago.
Is there a specific test for this TB, would I need to replace all the components, and finally how much could I be looking at spending? Thanks again
Expert:  GM Tech (Cam) replied 6 years ago.
Do you have a meter to do some of these test?
Sorry for the delays, I am still installing software to recover from a PC crash.
Customer: replied 6 years ago.
Thanks for your effort and information. The dealership called me and I gave some of the info I had and yours as well. I think we're going to have the TB cleaned and reprogram with software. They informed me the process will be around $200 more or less. Thanks for your info. It was worth the $18.00!
Expert:  GM Tech (Cam) replied 6 years ago.