I have exhaust entering the cab of the truck only when the heat, or defrost is on???

2002 CHEVROLET SILVERADO

132,000 MILES

MIKE02SILVERADO

MEMBER
2 POSTS

I have an 02 Silverado 1500 HD, with the 6.0.
Has 132000 miles, in great condition!!
The problem is, I have exhaust coming in through the vents, inside the truck??
I have had the manifold gaskets both replaced by a shop, and they said that would fix the problem. Well, it did not.

I have taken the truck to two other shops, and one replaced the cabin filter, and that did help.
So three shops total, and no results.
Any help would be great!!!

Please help!!

Thanks,
Mike

Dec 11, 2011 at 4:07 PM

JACOBANDNICKOLAS

✓ASE Certified Mechanic
110,194 POSTS

Mike, if it is coming in through the vents, there has to be an exhaust leak. Closely check to see if you can find anything. While the engine is running, have a helper plug the exhaust outlet to see if you can hear any leaks under the hood.

Dec 11, 2011 at 6:04 PM

MIKE02SILVERADO

MEMBER
2 POSTS

Thank you, I will try that asap.
Yes, I'm positive it is coming in through the vents, because if i turn vents off, the smell stops instantly.
I will try that today, and post my results.
Thanks again!!!
I really appreciate it!!
mike

Dec 11, 2011 at 6:10 PM

JACOBANDNICKOLAS

✓ASE Certified Mechanic
110,194 POSTS

Not a problem, Mike.

Dec 11, 2011 at 11:19 PM

CADIEMAN

✓ASE Certified Mechanic
3,544 POSTS

for this to happen you would have to have a massive exhaust leak under the hood under load and its getting in through the vent at the recerc. door. it isnt fully closing or it has a worn or damaged seal causes this to happen.or it isnt closing properly check the vacuum at the door sitting and driving.

Dec 12, 2011 at 12:24 AM

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