AC system not working properly

[SpeedJunki3]

To begin my question, the car that I am having issues with is a 2001 Pontiac Grand Prix gt with a 3.8L v6 non-supercharged engine. Recently my ac speeds stopped working and I tracked it to the blower motor resistor, which I replaced for $40 and the ac worked perfectly fine....for a couple weeks. Now it seems the resistor has blown out again as the only speed that works is the top speed, which just jumps over the resistor; however, now an even worse issue is that the blower motor fan is making a loud buzzing noise and the air pushed out of the vents gives off a somewhat burning smell, so I'm a bit worried to run my ac. I'm pretty sure this all is due to a faulty blower motor pulling too much amperage, however, I do not want to replace the motor and then replace the resistor AGAIN just to have the same problem. So I'm turning to you guys for an extra opinion? Also whatever you think the issue may be it would be very much appreciated if you knew anywhere to buy the parts very cheap but efficient and reliable since I am on a tight budget, but it's not necessary, thank you!

P.S. When the buzzing sound first started occurring it would "whine" or "buzz" for a bit while I ran the fan then turn off and it was fine, but now it continues to buzz and with the added burning smell I'm too worried to keep it running to see if it will stop or not.

[Stealthee]

That sounds like the blower motor is on its way out.

[brcidd]

W-cars are known for the rubber water deflector strip coming unglued and allowing rainwater into the blower motor- I'd check that first. It's under the windshield wiper cover on passenger side.

[Stealthee]

The 97-03 don't even have the deflector from the factory but one can be added.

[SpeedJunki3]

Originally Posted by Stealthee

The 97-03 don't even have the deflector from the factory but one can be added.

Ok, so I should be good to replace my blower motor and it should fix the problem correctly? There are no other issues it could be? Also, I know it isn't the deflector coming loose and water leaking in, even if my car had one because water would be flushed through the fan into my car since the blower is right under the passenger side, which no sign of water has come through.

[Tech II]

Yes and no...

It only takes a little water hitting that HOT resistor block, to blow it........

I would test the circuit first......remove the harness from the blower motor....first, look at the end of the harness coonector for melting or burning of contacts...if ok, look at the female connection on the motor, for melting or burnt contacts...

Attach a test light to the MOTOR harness connector contacts....turn key to on, turn HVAC head on to any mode, turn blower speed on low.......test light should be dim....as you progressively, turn blower speed for low to high, the test light should get brighter, until full brightness on high(should be as bright as if you put test light directly across the battery, for comparison)....

If the first four speeds do not light at all, but high does, the fuse is ok......remove the harness to the resistor block....remove test light from motor harness....attach one end to a good ground....attach other end to term C, purple wire of the resistor block harness......when you rotate speed knob to 4th speed, the test light will light....if it does, you need another resistor block.....also look for either a plastic defector on the air inlet out of place, or a rubber dam, that has fallen off allowing water to enter the fresh air duct.....to access this remove the passenger side wiper arm, and the retainers on the plastic cowl and lift up to inspect.....