Non Mercedes AC Question. Smells like toxic fumes. - PeachParts Mercedes-Benz Forum

pj67coll · #1 06-25-2018, 05:23 PM

I had the AC in my 2000 GMC Sonoma fixed a few months. Back. Replaced literally everything but the evaperator. New Condenser, Recieve dryer, orifice tube and compressor. It's been working great up till today. This morning I had a strange symptom. When I switched on the ac in the parking lot before leaving one of our campuses I heard and felt (Heard from the engine bay, felt thru the steering wheel) a groaning vibration which lasted about three or four seconds. This repeated itself several times during about a 30 second period then it stopped. Immediately there was an overpowering stench that I can only describe as a kind of cross between burning insulation, chemicals, and harbor mudflats at low tide. I guess the last bit wont mean anything to people who have never lived near the sea.

I drove back to the office and apart from the sickening smell the AC performed perfectly.

After a few hours I had to go out to another site and wen I started the car the awful smell happened immediately, though this time no groaning etc. The A/C still worked perfectly and is still Ice cold. But I can hardly drive from the effects of the smell.

Any ideas what could have happened? If the Compressor has developed a leak or some kind of internal seal burst etc could that be the issue? Anyone experienced a similar issue before? Just like some ideas before I call the shop. No sign of anything obviously wrong anywhere in the engine bay, or under the dash for that matter.

- Peter.

jcyuhn · #2 06-25-2018, 05:41 PM

Probably the noise and smell are from the drive belt slipping because the compressor does not want to turn. It will eventually break. Likely the compressor is failing, but could be an overcharge. Hard to say from here. Good luck.

P.C. · #3 06-25-2018, 06:33 PM

I vote for a compressor starting to seize...any warranty on the parts replaced a few months ago?

I remember renting a cube truck many years ago on a Memorial Day weekend. I drove down the road, entered an interstate, then slid the HVAC lever to "A/C". All Hell promptly broke loose, as the truck engine had a serpentine belt which ran every belt-driven item underhood. Courtesy of a seized A/C compressor and subsequent sheared belt, in one fell swoop I lost:

A/C
Power Steering
Alternator
Water pump function

I limped to an exit, and was a pedestrian, as I did not wish to fry the engine. I'm guessing that your Sonoma has a similar belt arrangement, so word to the wise....

pj67coll · #4 06-25-2018, 09:23 PM

Yes, it does have a serpentine belt and that's why I thought it might be possible to be the A/C. Because I couldn't think what might cause such a smell along with a weired vibration. However the thing is I've driven the thing for the rest of the day with the A/C off and the windows open. The smell is still there, though not as bad as with the A/C on. So I'm wondering if it might be something like the catalytic converter having failed. I'll find out tomorrow hopefully as I've just dropped it off in the shop after work. And I'll be in the 240D again tomorrow.

- Peter.

pj67coll · #5 06-28-2018, 01:13 PM

Turned out I got lucky. The heater core had burst. To fix that would be a ten hour labor job, have to remove the entire dash and half the suspension etc...

I told them screw it, just bypass the heater completely which they did at this cost of 140 bucks and a couple hours work. Now I'm back in business with Ice cold AC.

Dodged a bullet with that one.

- Peter.