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smell from a/c vents

avalancheg03

Full Member
Joined
May 7, 2003
Messages
47
I have noticed a smell when I turn on the a/c. It smells like piss or I don't know haow to describe it. Has any body have the same porblem how did you fix it. :D:
 
I had the same problem, but it would only do this after I didn't use it for a few days. Do you get it all the time? The only way I would describe it is exactly what you said "PISS" smell. I just thought it was normal.
 
In a humid climate like it is here in FL I have noticed this issue when using the vent w/out the A/C being on. Usually it is a musty smell like mildew. I have not tried this with the Av as I haven't had this problem, but in our VW I was told to try this by the VW service department and it worked...

Blow hot air on high in recirculate and spray some Lysol in the intake under the dash.

It worked, but I'm not sure I'd have the nerve to do this with my baby. Wait for some more opinions first and of course only try at your own risk ;) :)
 
That happened to me on my last vehicle. Stray cat sprayed by windshield area of car. When you turn on a/c ...wallah cat pee interior. Hate those damn cats..
Rich shouldn't you be working ??? >:D
 
I had this on my 2000 Tahoe. The dealer said there was a TSB on it.
They said mold or bacteria could grow on the AC coils in humid climates. Their fix, under warranty, was to spray some sort of cleaner/anti mold/anti bacteria solution on the AC coils. This fixed the problem for a while but it came back. Dealer said they would only do the procedure once under warranty, if I wanted it done again I would have to pay $.

In my opinion they did a poor job. It seems that when they sprayed the solution on the AC coils they did not clean the drain hole. It became clogged with the debris from the cleaning, causing the problem to only get worse over time. I never got water in the cab, but it would drip under the vehicle for two days after using the Air Conditioner.

Have not had this in the AV yet, but it is only 3 months old.
 
I was told it is mildew. If you turn on the heater and recirculate the hot air. It will dry up the mildew. It does work. Well it worked on my AV.
Musiks
 
try what musiks said ^

sounds like what I said but without the Lysol. Might just work :0:
 
i noticed it too. seems like it goes away when i have fresh HVAC filters in. when they are in there for awhile i smell the strange odor you all describe.
 
no filters in the '03, but I can see how old ones could grow stuff!

They got ditched by GM in '03 with the under hood light, tow package, blah blah blah :rolleyes: :rolleyes: :rolleyes:
 
Check to be sure the condensate drain hole is clear. If it is plugged the water will not drain out and provide moisture for mold to form in the A/C condenser.

HTH
John
 
AVid said:
Check to be sure the condensate drain hole is clear. If it is plugged the water will not drain out and provide moisture for mold to form in the A/C condenser.

HTH
John

How do I check that? do I use a wire from the engine side or in side the truck.
thanks
 
avalancheg03 said:
How do I check that? do I use a wire from the engine side or in side the truck.
thanks

You have to do it from the outside. There is no access from the interior. Be careful when probing, you don't want to puncture the condenser. On the right side of the firewall you will see a small pipe with a rubber boot attached. It is located directly under the accumulater bottle. The boot will be aimed down (or should be)and can be removed easily.
 
:8: I've been having the same problen in my Ford F150 work truck. I will try the Lysol in there today and let you all know how it turns out.
 
Wvusquatch said:
If it is a 2002 when was the last time you changed the HVAC filter?

No, My truck is an 03 and it was purchased earley February of this year 2003. I'll try the heater is kind of cool here in Houston and I roll my windows down on my way home.
 
How to avoid this is to turn the ac off, and continue to run the fan for a while. This will dry off the condensor, and you will not get that smell. Keep in mind that you will get the swamp-cooler smell as the moisture on the condensor evaporates back into the air.
Is it that you are turning the hvac system off, or turning off the A/C compressor. These are two different conditions. However, a wet condensor will stink. So, if you are just shutting off the hvac, then shut off the compressor by pushing the snowflake button, and wait a while before turning off the rest of the system......
 
avalancheg03 said:
AVid said:
Check to be sure the condensate drain hole is clear. If it is plugged the water will not drain out and provide moisture for mold to form in the A/C condenser.

HTH
John

How do I check that? do I use a wire from the engine side or in side the truck.
thanks
I wouldnt use a wire for the reason mentioned about poking a hole in the condesor. I would suggest using an air gun from an air compressor or if you dont have that use a can of electronic parts duster (the compressed air type) to blow up into the condensate tube from the engine compartment . I would also suggest running the heater on recirculate and then spray Lysol into the return under the dash. I have done this with as humid as it gets here in Dallas Ft Woth area during the summer and other than the musty smell when I had a water leak in the fender well. I dont notice anything from the A/C vents
 
WURTH makes a product which kills bacteria on the evaporator coil....

Also a cat may have really like your truck
 
Stop having sex with your air vents and it won't smell like piss anymore. LOL >:D

That's just too funny. I couldn't resist. No offense to anyone.
 
I have not had an odor problem in my Avalanche but I found this TSB some time ago. It seems that this one applys to all vehicles with AC odor problems,but I doubt many dealers really want to install the dryer kit. If anyone has a serious odor problem maybe this can help.


GM TSB:

Air Conditioning Odor (Install Kit) #99-01-39-004A
Air Conditioning Odor (Install Kit)
1993-2002 Passenger Cars

1993-2002 Light & Medium Duty Trucks

This bulletin is being revised to update the model years, service procedure, parts information and to add the GEO and Medium Duty models. Please discard Corporate Bulletin Number 99-01-39-004 (Section 01 - HVAC).

Condition
Some customers may comment on odors emitted from the air conditioning system, primarily at start-up in hot humid climates.

Cause
This odor may be the result of microbial growth on the evaporator core. When the blower motor fan is turned on, the microbial growth may release an unpleasant, musty odor into the passenger compartment.

There are several other possible sources of a musty odor in a vehicle. A common source is a water leak. Follow the Service Manual procedure for identifying and correcting water leaks if other odor sources are found. The procedure contained in this bulletin is only applicable if the source of the odor has already been determined to be the HVAC module.

Correction
To remove odors of this type, it is necessary to eliminate the microbial growth and prevent its reoccurrence. To accomplish this, the following steps must be completed:

Apply evaporator core Cooling Coil Coating (Aerosol 6 oz), P/N 12377951 (AC Delco? 15-102) (in Canada, use P/N 10953503) or Cooling Coil Coating Kit with Extension Nozzle, P/N 12346391 (AC Delco? 10-120). Refills are available for the Cooling Coil Coating Kit with Extension Nozzle, P/N 12346391 (AC Delco? 10-120). Refer to the chart below.
Install the Electronic Evaporator Dryer, P/N 12497910 (AC Delco? 15-5876).

Important
The Cooling Coil Coatings listed above are the only GM approved products for the disinfection and long-term control of evaporator microbial growth.


The Cooling Coil Coating will disinfect the evaporator core and help inhibit the growth of future mold and mildew.

The Electronic Evaporator Dryer will activate when the ambient temperature near the module is above 16? C (60? F) when the vehicle is started up. Approximately 30 minutes after the vehicle has been turned off, the blower will activate for 10 seconds every 10 minutes for 2 hours unless the vehicle is restarted. If a restart occurs, the Electronic Evaporator Dryer module will reset automatically. This on/off blower activation will dry the evaporator core and case reducing the chance of reoccurring A/C odor. The Electronic Evaporator Dryer is self fused and has a battery rundown protection feature that inactivates the dryer if voltage drops below 12.5 volts.

Service Procedure
Visually inspect the air conditioning evaporator drain hose for obstructions and/or working condition.
The cooling coil coating fluid must be applied to a dry evaporator core. Apply coil coating fluid as described in the instructions supplied with the kit. In some instances, the blower motor resistor can be removed for this spraying operation. If used, the opening can be taped over and the nozzle inserted through a hole in the tape. The kit instructions identify a drilling procedure to apply the coating fluid. When using this type of procedure, care must be taken to avoid evaporator damage and any holes must be properly sealed. Some coating fluid may overflow from the drain hose.

Important
When installing the Electronic Evaporator Module, you MUST use the included electrical splice connectors to ensure a proper splice.


Complete detailed installation instructions and wire connectors are supplied with the Electronic Evaporator Dryer. The ground wire should be attached to a body ground source. If any other wire splicing procedures are needed, follow the wire repair procedures in the Electrical sub-section of Body & Accessories in the appropriate Service Manual. If required, the evaporator dryer can be installed underhood away from extreme heat conditions (i.e. exhaust manifolds) and/or water splash areas. In all cases, the evaporator dryer module must be secured with a Velcro? strip (not included in the kit), or you may use the integral hooks to utilize tie straps. Using a Velcro? strip is preferred as the use of the integral hooks may cause rattles.
When the installation procedure is complete and power is supplied, the module will self-test. Thirty seconds after power is supplied, the high blower speed will be activated 3 times (for 2 seconds per cycle). When the test has run, install the Electronic Evaporator Dryer label on the blower motor case in a visible area.
Parts Information
Part Number
Description

12377951

(AC Delco? 15-102)
Cooling Coil Coating (Aerosol 6 oz)

12346391

(AC Delco? 10-120)
Cooling Coil Coating Kit w/Extention Nozzle

12346390

(AC Delco? 10-121)
Refill for Cooling Coil Coating Kit

12497910

(AC Delco? 15-5876)
Electronic Evaporator Dryer Module Kit


Parts are expected to be available from GMSPO, 6/4/01.

Warranty Information
For vehicles repaired under warranty, use:

Labor Operation
Description
Labor Time

D3316
Apply Cooling Coil Coating/Install Electronic Evaporator Dryer
0.8 hr





 
Trafficman said:
:8: I've been having the same problen in my Ford F150 work truck. I will try the Lysol in there today and let you all know how it turns out.


It turned way cold now so there is nothing I can do to find out because the f word does not smell any more and I did not spray the lysol in there. Also I will be getting a new F-150 in march before it turns hot. Sorry... :-[
 
GM has some sort of no-stunk stuff..
Look here:
http://service.gm.com/gmtechlink/arcv_pdf/3_02_e.pdf
 
I've also seen tech notices that say you can program the HVAC to run for a short period after the vehicle is shut down. This apparently allows the condenser fins to dry out because if you shut the AC off with them damp it causes mould to grow and the smell that you might be getting is that.
 
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