Hello,

I have a 1982 Firebird Pontiac Trans am 4 barrel carb set up. And for some reason when the AC is on, while the car is running(idling), it seems to shut the car off.

And I dont know why? Do you guys have any suggestions on what should be done?

Thanks all

 

First thing I would check is the battery cables, especially your grounds.

 

If you have a stock engine, carb, a/c set up you should have a hi-idle solenoid
that steps up the idle (to prevent stalling) when the heater control selector is
moved to the a/c or defrost settings.

Its mounted on the carb. You should check to see if its disconnected/broke/
misadjusted or even missing.

Test for power at the idle solenoid plug with ignition on and the a/c heater control
is moved to the a/c position.

Post results

 

Yes, maybe you are right! I just had a tune-up on the car and they did mess with the carb. But FYI, the carb is not run by the the ECM at all and so there are no electronic wires going to the carb. But I am a begginer when it comes to the carb. Can you direct me on where to look for this idle solenoid plug? What does the plug look like? Can I see it by just removing the the carb top and air filter? And where is it in relationship to the PCV filter?

Thanks friend!

 

Is it a stock E4ME quadrajet ?

There should be a solenoid with a electric plug attached to it.
A stock E4ME carb should have a couple of electric plugs to it
and yes its computer controlled more or less..................

Look at the pic below. Note the gold colored can looking thing on the right
in front of the throttle linkage. Note the plug and wire attached to it.
Thats the idle solenoid. It kicks up the idle when the a/c mode is selected.

Note the other TWO wires also hooked to the carb............

IF yours is stock it should look exactly like this!
If NOT then somebody cobbled up your set up..................

 

Even if someone changed it to a non-feedback carb, the step up solenoid can still be used. It likely was, and if the problem started after the tune up, all you likely need is a proper adjustment on the solenoid.

 

Unless they swapped the CCCarb out fora non CC carb, and took off "all" the electronics, including the high idle kicker. You definitely need it, it holds the throttle open a bit to keep the RPMs up when you run your AC.

 

OK.....Sorry "Sonjaab" it took me a while to get back with you.....been in school studying

Thank you for submitting this picture of the carb to me, it is sooooo halpful!

YES I do have a stock 4 barrel carb, but I dont have a Computer Command Control System. My carb does not have this set up. I have the vacuum advance system! So if this makes a difference, then let me know.

But I also wanted to relay to you that not every time will the car shut off at idle(with engine on and placed in park) when I turn the AC on. It seems that the colder the car is, the more often it would turn off under idle. Or it seems to do this when car is at lower idle. But the idle is set tp stock, so it is not low!

What do you think?