2003 Chevy Problem

[deerejohn]

Would like to get some advice on a problem

This morning had to jump start my p/u ran fine to work and once there I installed a new battery and the funny stuff started happening the idle is up and down the blower motor speeds up with engine rpm and the air is being diverted from defrost vents to air cond vents on its own the ac compressor is not engaging any suggestions

 

2003 chevrolet 1500

5.3 v-8

85000 miles

[GMTRUCKTECH]

Do you have a electronic throttle body?

[deerejohn]

I really thought I did I thought they were all electronic ?? How can I tell for sure?

[bossier62guy]

I really thought I did I thought they were all electronic ?? How can I tell for sure?

 

If it has a throttle cable hooked to it or not. If no cable is there it's electronic.

[deerejohn]

yes it is electronic

[GMTRUCKTECH]

The actuator binds on the throttle bodys causing a unstable idle. I have tried cleaning them and so on with no luck, your best bet is to replace the t/b and gasket. Also there is a update for pcm to improve idle stability I would highly recomend doing both.

[ChevyTech007]

If all this started happening immediately after the the battery replacement, I would disconnect both battery cables and hold a jumper wire across the cables for a few minutes to completely power down the system. Reconnect the battery and restart. Do not touch any of the A/C controls for a few minutes after restart.

[GMTRUCKTECH]

At work today I get a 2003 silverado with the complaint customer: installed new battery now vec idle is unstable and vec wants to stall in gear a/c also inop. SO I put a new electronic throttle body on it and updated the computer like I always do and low and behold it fixed it. I just thought of this thread when I read the repair order.