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Foam in AC Vents

Hi everyone. Perhaps someone will have an idea. There are bits of foam blowing out of the ac vents on my chevy pickup. Took it to the shop. They checked it over and said that the AC is functioning properly no problems with the system. The foam they state is coming from the doors inside of the ac system and suggested that I ignore it. I looked closer inside the vents with a flashlight and I do believe they are correct from what I saw. It is messy as it is greasy if squished. I am wondering if anyone has tried to use an air compressor to blow out the vents and remove as much of that junk as possible and was it very successful? That is our idea and we plan on trying it later today or over the weekend. If not, did that junk ever cease to blow out on its own eventually? Thanks.

The same thing happened on my 1993 Caprice and my 2000 Blazer as the foam gaskets between the duct work and the dash vents aged and deteriorated. I have to agree with the shop on this one.

Ed B.

Thanks Ed B. Did the stuff eventually stop blowing out of your vents? I would think there can only be so much in there, that is why I am going to try and blow out as much as possible. Clair

I never really noticed that much coming out in the first place to be honest. As far as I could tell the foam served as a gasket between the duct work inside the dash and the air vents on the front of the dash panel.

I used a vacuum cleaner on the dash vents to clean out the old foam. I would be afraid the high pressure of a compressor could damage the blend doors inside the dash.

Ed B.

It will eventually stop coming out on its own, because there is only so much foam in there to be blown out. The alternative is to have the foam replaced, which is costly because they have to disassemble a bunch of stuff to get to it. I’d just ignore it, and pick up the little chunks when they blow out.

Leaving the technical stuff to other posters here, who definitely have MY respect insofaras they know what they’re talking about, I’m still going to say this:

Okay, so you take the shop’s advice and let the foam eventually blow itself out. You may be paraphrasing the shop’s words unfairly here, but if a shop told me “They checked it over and said that the AC is functioning properly no problems with the system. The foam … is coming from the doors inside of the ac system and suggested that I ignore it,” (and just like that), I wouldn’t care much for their attitude. Sounds kinda degrading.

Maybe the shop has some really good people there, and maybe I’m reading too much into that statement, but I may be wary of that shop in the future. If they’re condescending to you about a foam coming from the air vents, what will they try to do if you should need something like a head gasket?

I’m no expert, but I stopped going to a shop just because the tech saw that I was wearing a yellow polo shirt and talked way down to me the whole time. I was just there for tires. “Balance them, put the stems in, get them back on the car, and let me pay you.”

Might be a little rough on the shop. I’m sure the next sentence was that we can disassemble the dash and duct system for $800 to replace the 50 cent strip of foam if you want. Customer’s choice, or live with bits of foam blowing out.

^^^ Fair enough. Just to reiterate, I very well may have read too much into that statement, or maybe the shop’s words were being paraphrased into a different context. So, OP should take my previous comment with a grain of salt.

The foam is greasy if squished? How old is this pickup? Is the engine compartment prone to fumes from various car fluids? Are you slowly losing any car fluids?

Greasy isn;t normal. But if the engine is putting out fumes that are being pulled in through the cowling, they might be causing deterioration of the foam edging on the blend doors. Also, if your heater core is leaking that could also be the source of your greasiness and deterioration. It may not do you much good to change the foam gaskets as long as the source of the fumes remains.

This type of black foam deteriorates into a gooey/sticky material. I saw this with my Caprice and Blazer and even in my Canon AE1-P film camera. I don’t think it’s external contamination, just old age.

Ed B.

Oh well. Never seen it myself, but I learn something new every day.