Engine/Transmission (1998.5 - 2002) Cab Odor

[larneub]

About 2 years ago I started getting a vinegar like odor in my truck during the summer after the AC had been off a day or so. About a year ago, I started getting an oil odor in the cab also. This coincided with about the time I started adding 2 cycle oil to my fuel so there may be a connection. I have moved my blow-by hose to exit behind the cab and don't have much oil residue on my fan or radiator like I did before, but the oil (and vinegar) odor is still present. Any ideas or solutions? There isn't any oil dripping from either my engine or transmission. I cannot find a source for either smell.

 

[DCreed]

do you still have the rubber hood seal across the cowl?

 

[larneub]

Yes, it's still in place.

 

[viper700]

I had a bad smell last year in my 04. 5. Dealer said to run A/C on outside air not inside air. You can see on Panel where it points to outside or recurculate. What you are smelling might be stagnent moisture from A/C residue.