I know this is going to sound stupid, but I thought it was worth posting. I have an 01 Excursion with a 7.3. Only perf mods are a 6637 kit and a Superchips 1705 on tow perf setting. The X runs well, no missing, etc. Starts up fine and gets around 14-15 mpg everyday driving and 18-19 mpg on a trip. The issue is the very strong exhaust smell (not raw diesel). Just starting it in the garage will make it burn your eyes idling. No smoke idling. My wife was following me the other night and she even commented that the X has a very strong exhaust odor going down the road. I dont have gauges yet and for that reason i dont tow with it. I had an 03 F250 with the same mods and i dont remember noticing it. It reminds me of an over jetted carburetor on a gas motor. I have no uppipe leaks and a new ICP sensor for what it's worth. Like I said, it has about the amount of power I think it should have, it just flat out has a strong exhaust odor.

 

Subscribing! Same exact issue here.

 

I've had the same issue but blamed it on the station I purchased the fuel from . Do you get fuel at the same place all the time ?