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It barely cools down the car. When I bought the car 9 months ago one of the things I noticed is that the AC blew weak. It comes out the vent cold though. I thought maybe that’s how G8’s are. Then I test drove a GXP this weekend with 30,000 miles at a dealership. That AC blew so much stronger compared to mineSo now I know for sure mine has an AC problem.

I figured it could be the blower motor, blower motor resistor, or blend door actuator. I don’t get any whining noise or noise from the glove compartment so the blower motor is not making any noise.

I changed the cabin air filter and got all the leaves out of there. That didn’t change anything.

I don’t want to just start part changing because that can turn into a lot of extra time and extra money than what is needed.
Any ideas?
 

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Is the heat weak (fan speed)? When the blower motor resistor fails, oftentimes the fan defaults to full speed and the blower motor won't run on certain settings. Do you have a manual or automatic climate control system? The blower motor has a relay (R9) located in the instrument panel fuse block (inside). Could easily swap it with a known working relay to verify it's operation. also, there's a fusible link (FL9) located in the compartment fuse block. Should be able to hear the fan speed change as commanded by the head-unit. If not, the problem could lie within the blower motor, wiring, or the head-unit itself. Will require a little troubleshooting to rule out various aspects of the system.
 

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If you want to see how efficient your fan is, give this a try. If its warm to hot outside, turn the A/C on with an AUTO MODE selected, an pick a random temp setting (say like 68). If the fan speed feels weak to you, start pressing the + side of the fan rocker button. That puts the A/C into the semi automatic mode, an displays what the current fan speed is set at. The fan has 20 speed settings. You can use the fan rocker button an peck away at the up or down speed as you desire. The fan speed change is displayed as you do this It should give you a good idea if the fan itself is performing as it should. Selecting outside air source vs recirculate mode is also a smarter move (in my opinion) to get the coldest air. If by selecting all the various fan speeds (with instrument panel vents selected) you can tell that the fan appears to be OK (volume/flow wise), maybe your A/C system refrigerant charge is down a little.

The fan speed is controlled by changing the voltage pulse time (on vs off) to reflect the actual speed of the fan at any time.
 
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