I am having an issue where my vehicle will lose power and stall at idle after the AC has been on for a while. I have a 2004 MT RX-8 with 118k miles on it. I have to wait until it has cooled down a bit while off then it will start back up just fine and drive normally. If I don't have the AC on at all and just the blower motor, it'll run fine through the entire trip. If the AC is active, it blows cold.

The temp gauge doesn't move, and through Torque (Bluetooth OBD2 Android App) it says the coolant sits around 209F. The voltage reads 13.8 while the car is running, and when not running 12.5. There is no CEL/MIL when the car loses power.

Things I've done thus far to help remedy the situation:
The cat was clogged so I replaced that.
Cleaned the ESS.
Cleaned the MAF.
Cleaned the TB.
Checked all fuses.
Checked the coolant and oil.
The coils have been changed 20k miles ago, the plugs and wires 4.5k miles ago.

I am aware that I am missing doing something really simple in diagnosing this, so any help would be highly appreciated.

 

The A/C compressor will stall the car if working at a very high pressure (from high operating temps). I see your in Arizona, what was the ambient temp when this was happening?

Sometimes this is a sign of a A/C blockage, (rarely) a failing compressor, or an over-charged A/C system.

EDIT: Could also be the compressor clutch.

 

Mine stalls when the a/c is on specially when the temperature is over 100 degrees. I usually do not turn it on now even though its still hot, and i could drive it without getting stalled anymore. I replace my coils, plugs, and wires a few months ago, but haven't checked my cat for issues yet though, will try to do it soon.

 

So far I've seen the issue happen when it is over 100F outside, and since I've had the problem I've not driven the car when it is over 100F at all possible. I'll check the charge on the lines, probably while it is warm outside to see if that is it.

Is there ways I check for blockage? Would that just be a extremely high or low pressure when I check the charge? The clutch seemed fine when I did my preliminary checks, but I'll look more into that as well.

Thanks for your time and suggestions!

 

Looks like it was an overcharged AC system. Was cooler outside so I didn't have a chance to test it until just yesterday.

Thanks again :D