Mechanics

CHEVY EXHAUST SMELL IN INTERIOR

1968 Chevrolet Chevelle

Smells problem
1968 Chevy Chevelle V8 Two Wheel Drive Automatic 140000 miles

Hi:
I have a 1968 Chevelle Malibu which I restored (frame on). I installed new floor pans, trunk pans, inner rear wheel tubs, quarters, trunk floor extender corners, as well as a bunch of braces. Seam sealer was used on all mig welded joins. New noise reducer insulation on the floor, new carpet. New exhaust from front to back. New manifold gaskets. I am runing a 403 olds with TH350 trans. I get an exhaust smell in the car while driving around 30 to 40 mph with the drivers window about half down. There are no hoses leaking on the engine, no exhaust leaks and the tail pipes extend 3 inches or so past the rear bumper. I have checked for entry points all around the trunk, quarters, wheel tub area, and there are no holes anywhere. The only possibilitie is the trunk cover weather stripping which I will be replacing this spring. I know that there is a vacuum created behind a car as it travells. Somehow the exhaust is getting sucked into my car. Can you suggest something I may have missed. Thanks !
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68malibulee
March 1, 2010.



First if you spot mig welded you should pound all the betal together and then use seamsealer wherever you cut the old floor out. Also there may have been rubber plugs for drainage on the floor pans and you never reinstalled them. Theexaust may be coming from the heat valve on the passenger sideor you could havea slight crack in one of the manifolds. Recheck your floor pans for sealer and connections by the engine. There should be smal hoes in the muffler on the bottom for drainage of condensation an you may have turned those up instead of down. Use a mirror to see if they are in the correct position.

Hmac300
Mar 5, 2010.
From all the work you did, you probably undercoated the car?
Check to see if the exhaust system has undercoating on it or is too close to the floor, cooking the undercoat.
Check your firewall for holes or holeplugs missing, there are seals for the steering colum, brake pushrod, heater box and accelerater cable that could need replacing.

Tiny
Mr Ted
Mar 11, 2010.