TR224 Killed my MPG
I smell gas on cold starts too, but that goes away as the engine gets warmer.
If you have cats in a stock location, I found that it is harder to get an accurate wideband reading because you are mostly likely measuring after cat A/F. I'd take a look at your LTRIMs and see if they are whacked.
I'll put it this way, it took me and a friend 2-3 hours driving around to work on my drivability and I gained a lot of part throttle power and my mpg went up 2-3 mpg overall.
-Geoff
The Best V8 Stories One Small Block at Time






