Car stalls when using defrost/ac

[Blast47]

1999 CSVT, No mods -

So, my car was making a strange "psssst" noise when I started it last week after turning on the defrost. I drove to work, and omw there - the car died when I stopped at a light, a kind of sputter stop like if I let off the clutch in gear. i restarted the car, and got to work. from this point on - whenever I turn on the panel/defrost, defrost, ac, max/ac the car stumbles and dies. I figured maybe the assembly belt was going bad or something...since that's an easy fix- so yest. I replaced that belt with a new one - made sure the tensioner was positioned right, etc. Nope - same problem. The pssst noise is constant when I turn on the car - defrost, ac, or not...

I dunno if the ac compressor gets engaged when using the defrost?? So possibly that piece is going bad? Dunno - :shrug:

 

[myconsvt]

i would check you ac compressor, the clutch is prob siezed up. and yes the compressor kicks on for the defrost

 

[Blast47]

Is there a 1 person way to check this? Or do I need two people (someone in my car turning on the defrost, while I watch the clutch)

If it is in fact the compressor - can I just change the clutch/pully part, or do I need to change the entire compressor + clutch assembly?

 

[Redlineracer12]

i would check you ac compressor, the clutch is prob siezed up. and yes the compressor kicks on for the defrost

I would start with something more basic... Like how does the car run without the AC/defrost on? If it always stumbles a little bit, it's going to be considerably worse when the AC compressor engages. My car would do what you're describing last summer but it ended up being a faulty IAC valve. It would stumble a lot when I pushed in the clutch while coming to a stop, killing occasionally. When I flipped on the AC it would stall almost instantly when I pushed in the clutch.

 

[Blast47]

I would start with something more basic... Like how does the car run without the AC/defrost on? If it always stumbles a little bit, it's going to be considerably worse when the AC compressor engages. My car would do what you're describing last summer but it ended up being a faulty IAC valve. It would stumble a lot when I pushed in the clutch while coming to a stop, killing occasionally. When I flipped on the AC it would stall almost instantly when I pushed in the clutch.

It runs just fine... 'cept that constant hissing noise. I feel no power loss, no stumbling or anything else when it's off

 

[zorrex]

It sounds like you have a vacuum leak, causing the hissing. Do you have an CEL's?

 

[CSVT1214]

I'd say the A/C compressor is seized up. The clutch is attempting to engage with too much resistance causing the motor to stall.