A/C shuts off when Accelerating

[TucsonBird]

Re: A/C shuts off when Accelerating

no, what he said was correct.

Umm I can tell you from experience that revving the crap out of a car with the A/C on will **** up the compressor if the PCM doesn't switch it off as it does in our cars.

Could be that they make heavy duty ones that can take the abuse but not likely.

The PCM turning it off also helps to not rob power, but both of these reasons are valid.

[zlexiss]

Re: A/C shuts off when Accelerating

Ok, two things here.

The A/C compressor disables under a few situations (looking at my HPTuners parameters). These are "or", so any will shut it off:
RPM above 5440 (possibly to protect the unit re: victimization)
TPS above 90% (extra WOT power at any RPM)
IAT above -40*F (again probably self-preservation)
ECT above 257*F (probably to avoid further engine overheating)
Volts below 9.5V (prob several reasons)
Plus disabled for 3.75 seconds after startup

Hope that cleared up some of the arguments.

But this isn't what 99marodriver originally asked. When he gives it some gas his top vents stop blowing air (whether a/c or vent is being used), which is a vacuum issue. The vent flappers use vacuum to hold them open.

There's a check valve and a small reservoir to keep them open during some WOT. It's normal to lose the vents after a long WOT, but if they're going away right away or even at moderate throttle either the check valve is bad or there's a leak somewhere.