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1998 Chevrolet Silverado Repair Question


Topics covered: Smell, Heater, Exhaust.
Mileage: 51,480 miles.

Asked on November 26, 2010

Exhaust smell when heater used.

I have a 1998 Chevy Silverado 4x4 and when I run the heater I get a strong exhaust oder in the cab. I have no exhaust leaks and it does not happen with the AC, just the heater. I get the smell sitting still or moving. Do you have any idea what could be causing this?
Avatar Asked by EODWILLIE7

Answer

Replied on November 26, 2010

Sometimes mold grows inside the HVAC unit and you'll get strange odors. However, if this was your case, you should smell it with a/c on as well.

Sometimes what smells like one kind of odor to you will smell different to someone else.

You may have a slight leak in the heater core or hose that's causing this smell.

Also, I've seen many strange things show up inside of cars. You could try removing the HVAC unit and looking around inside for the source of the smell.

Tiny Answered by Ernest Clark (expert)
1,762 answers provided