Musty smell out of AC at start up.
#1
Drifting
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Musty smell out of AC at start up.
2011 GS with 3700 miles. It is FL therefore AC is always on auto. Lately when I start the car first thing in the morning I get this musty smell out of the vents for few seconds than it clears up and I am OK for the restarts during the day, if any. I pulled out the cabin air filter to examine, darn this thing is flimsy for a $43 part, I do not think it is a problem but I am going to replace it anyhow. Obviously this smell is coming from the AC heat exchanger within the car. Has anyone had the same issue and how did you eradicate this problem?
I never had this problem with my Volvo during the last 140,000 miles, and the vette is also parked in the same garage as the Volvo. However the vette is covered with a car cover, volvo is not. The mildew from the cover?
Thank you gents!!
I never had this problem with my Volvo during the last 140,000 miles, and the vette is also parked in the same garage as the Volvo. However the vette is covered with a car cover, volvo is not. The mildew from the cover?
Thank you gents!!
#2
Instructor
This has been a problem with earlier vettes, but I thought this was solved by your model year. Take it to the dealer, they can activate the after blower.
#3
I bought the cabin filter from Amazon for $15.00, took all of 2-minutes to install, did it help, wife says maybe not.
2011 GS with 3700 miles. It is FL therefore AC is always on auto. Lately when I start the car first thing in the morning I get this musty smell out of the vents for few seconds than it clears up and I am OK for the restarts during the day, if any. I pulled out the cabin air filter to examine, darn this thing is flimsy for a $43 part, I do not think it is a problem but I am going to replace it anyhow. Obviously this smell is coming from the AC heat exchanger within the car. Has anyone had the same issue and how did you eradicate this problem?
I never had this problem with my Volvo during the last 140,000 miles, and the vette is also parked in the same garage as the Volvo. However the vette is covered with a car cover, volvo is not. The mildew from the cover?
Thank you gents!!
I never had this problem with my Volvo during the last 140,000 miles, and the vette is also parked in the same garage as the Volvo. However the vette is covered with a car cover, volvo is not. The mildew from the cover?
Thank you gents!!
#4
Pro
I thought this was pretty much normal. I have not really noticed it in the Vette, but haven't really used the AC all that much. However, having driven in cars for the last 40 + years, this seems to be normal, happens in most of them including my 2010 Camaro, my 2003 VW, my wife's 2008 Mazda, my earlier 2004 Toyota truck, not to mention my previous 4runner, my Celica, my Mitsubishi ...etc.
So I can't believe every one of them had an issue. Did they?
I'm just talking a brief clear up of the system and a slightly musty smell as the vents clear out...nothing like a dead animal or anything like that.
So I can't believe every one of them had an issue. Did they?
I'm just talking a brief clear up of the system and a slightly musty smell as the vents clear out...nothing like a dead animal or anything like that.
#6
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After I posted this (I jumped the ship too quickly) I went to check my shop manuals (which I spent mucho money on) and sure enough they were odor diagnostics and a procedure detailed for for correcting the odor under HVAC section. I am supposed to get this aerosol from GM, drill a small hole in the hose between the blower motor and the evaporator, and while running it on high heat, spray it, let it seat for 5 minutes and than again run it on high heat for 5-10 minutes to dry it out (and not forget the replug the hole). There is slightly more steps involved, if and interest I will copy it here for others benefit.
Yep, definitely DIY job, not even worth the trip to dealer, they will probably never plug the hole scratch the door sills, kick the doors with their dirty boots, mess up my carpet and try my launch control in their parking lot or maybe even worse.
Thank you for the tip hervettemyviper $13 at amozon ha!...that was worth putting up this post! (I looked at other online GM warehouses but what a scam, by the time you add the shipping, it is within $3 of the dealer price, and still expensive!
Regardless, thank you for the replies!...
Last edited by gsflyer2011; 02-29-2012 at 06:54 PM.
#8
Drifting
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No problem at all, here it is.
Need a Deodorizing aerosol kit (probably from GM, no part numbers were supplied)
1-Make sure plenum and fresh air cabin filter is clean and free of debris
2-Disable AC compressor clutch operation by disconnecting the clutch coil electrical connector
3-Start engine select warmest temp setting select recirculation mode, run blower motor on high for 10 minutes.
4-Locate an area in the AC duct between the blower motor and the evaporator core downstream of the blower motor.
5-Drill 3.175 MM (0.125 in) hole where the hole will not interfere with or damage any of the operating parts of the system (blower or evap).
6-Select Max blower speed, insert the deodorizer extension tube into the hole to the mark on the extension tube. Use short spray bursts and vary the direction of the spray for 2-3 minute period.
7-Shut Engine off, let the vehicle sit for 3-5 minutes.
8-Seal the hole with a body sealer or RTV gasket material.
9-Start the engine and operate the blower motor on high for 15-20 minutes to dry.
10-Reconnect the AC compressor clutch coil electrical connector
12-Verify proper AC clutch operation.
I guess it is best to keep both doors open while the spraying and drying be done so that the car will nor smell like a cat house or a hospital..... It does not specify this action.
I am going to try the first few steps (up to 3) first to see if I can just dry up the evaporator first, who knows that might be just enough as the smell only lasts few seconds....
Need a Deodorizing aerosol kit (probably from GM, no part numbers were supplied)
1-Make sure plenum and fresh air cabin filter is clean and free of debris
2-Disable AC compressor clutch operation by disconnecting the clutch coil electrical connector
3-Start engine select warmest temp setting select recirculation mode, run blower motor on high for 10 minutes.
4-Locate an area in the AC duct between the blower motor and the evaporator core downstream of the blower motor.
5-Drill 3.175 MM (0.125 in) hole where the hole will not interfere with or damage any of the operating parts of the system (blower or evap).
6-Select Max blower speed, insert the deodorizer extension tube into the hole to the mark on the extension tube. Use short spray bursts and vary the direction of the spray for 2-3 minute period.
7-Shut Engine off, let the vehicle sit for 3-5 minutes.
8-Seal the hole with a body sealer or RTV gasket material.
9-Start the engine and operate the blower motor on high for 15-20 minutes to dry.
10-Reconnect the AC compressor clutch coil electrical connector
12-Verify proper AC clutch operation.
I guess it is best to keep both doors open while the spraying and drying be done so that the car will nor smell like a cat house or a hospital..... It does not specify this action.
I am going to try the first few steps (up to 3) first to see if I can just dry up the evaporator first, who knows that might be just enough as the smell only lasts few seconds....
#9
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The best thing to do is to go to the dealer and have them implement the afterblow. This runs the blower for a few minutes after you turn the car off and helps evaporate the condensate that is on the evaporator core. This isn't an issue restricted to any brand car. When you have evaporator coils that are damp with moisture that condensed on them and then let that moisture sit inside a dark area that gets nice and warm after the car is turned off you will get mildew. You can combat it by spraying stuff inside the evaporator or you can dry out the evaporator by running the fan for a while after the car is shut off. I prefer the non chemical solution.
Bill
Bill
#10
Drifting
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The best thing to do is to go to the dealer and have them implement the afterglow. This runs the blower for a few minutes after you turn the car off and helps evaporate the condensate that is on the evaporator core. This isn't an issue restricted to any brand car. When you have evaporator coils that are damp with moisture that condensed on them and then let that moisture sit inside a dark area that gets nice and warm after the car is turned off you will get mildew. You can combat it by spraying stuff inside the evaporator or you can dry out the evaporator by running the fan for a while after the car is shut off. I prefer the non chemical solution.
Bill
Bill
#11
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Common problem on the 1997-2004 Corvettes. I have done the spray method and it cures the problem.
#12
Pro
Just a tip, if you want a new filter, get the Purolator partnumber C25623. They are just as good if not better than the GM one and can be found at Advance Auto Parts etc for about @ $10...
Sonny
Sonny
#13
Drifting
Had the same issue on my 08 vert about a year ago. GM makes a carbon cabin filter(part # 15861929) I bought from gm partshouse. I sprayed some a/c deodorizer I had from toyota in the cabin filter cavity and by the air intake under the hood. no problem since.
#14
Melting Slicks
The best thing to do is to go to the dealer and have them implement the afterblow. This runs the blower for a few minutes after you turn the car off and helps evaporate the condensate that is on the evaporator core. This isn't an issue restricted to any brand car. When you have evaporator coils that are damp with moisture that condensed on them and then let that moisture sit inside a dark area that gets nice and warm after the car is turned off you will get mildew. You can combat it by spraying stuff inside the evaporator or you can dry out the evaporator by running the fan for a while after the car is shut off. I prefer the non chemical solution.
Bill
Bill
#15
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Thanks Bill!, I agree with you avoiding chemicals unless it is absolutely necessary, add dealers to that list. That is why I want to do steps 1-3 while I am driving the car and the heater is putting out full to dry up the evap. This sounds like very similar to a what dealer would do, except I totally (and deeply) despise dealers, the only time I have to go to them is to buy one, and that even with great deal of reluctance!..
Bill
#16
I had the same problem on my 08, GM makes a deodorizing spray you can spray into the intake. I also found a sponge like filter that fits over the intake just below the drivers side wiper. I think it helps keep outside water out of the system. I got it at Mid-America. It also keeps larger debris out of the cabin filter.
#17
Melting Slicks
I have used a product like this before. It comes with a long tube that you can feed through the dash vents. It worked OK on my Pontiac. In my case, I think I'm going to have to pop out my blower and literally saturate the evaporator with this stuff. My smell goes away for about a week...then it comes back.
I do follow the tip of turning off the AC (but keeping the blower on) for the last few minutes before I'm done driving somewhere. That definitely helps.
I do follow the tip of turning off the AC (but keeping the blower on) for the last few minutes before I'm done driving somewhere. That definitely helps.
#18
Burning Brakes
You're doing the right thing by deodorizing the system. To keep it fresh turn on afterblow and be sure the condensation drain hole is clear so all the water can drain out. That drain hole is not in the best location so make sure it is clear.
I have a copy of the TSB if you are interested.
I have a copy of the TSB if you are interested.
#19
Burning Brakes
I haven't had my car very long, but from previous cars I've noticed that leaving my ac on max or recirculate causes bad smells over time. With it on auto, I am constantly shutting it off when I see it on in hopes that I'll avoid the issue that you're experiencing.