LesPaul

is this normal... i just ordered a new tune for the headers hope it will fix it.....
exhaust smells really rich... i have a leak due to a broken bolt not sure if it would cause rich a/f ratio.... also have a ORY so not sure if no cats would cause it to smell rich..... seems like im having bad gas millage but it could all be in my head let me know guys thanks

thunder550

iTrader: (70)

No cats will definitely change the smell. If you truly have an exhaust leak, your O2 sensor will detect more air and think the engine is running lean, and will richen it way up until the O2 is reading at stoich. This may be what is happening.

JT-bo

if you had cats before then yes you would definatly smell a difference because there's no catalyst to "clean" the exhaust as it was before

bud8fan

iTrader: (9)

question...if you take out the cats and hook up the front 02 sensors at the headers and then put in one single big cat in the pipe after the y...the back 02's are tuned out....would this work?

thunder550

iTrader: (70)

I dunno if the cat would get hot enough to do anything....why wouldn't you just go catless?

bud8fan

iTrader: (9)

was just thinking outloud....i thought the older setups had only on cat....
i am catless right now....

thunder550

iTrader: (70)

Gotcha

Beastofa327

Thats right, like JT said theres no catalyst and the chemical elements from the gas aren't being caught.It's gonna smell richer till you get a tune. if you run 93* it won't smell as rich as 89*

BigRed53

when u install lt's you need to get a tune regardless, i had a bad problem when i installed my pacesetters, my truck started getting multiple missfires, truck was shaking, when i put it in gear, it died. Wasnt pleasant at all, but i switched my wires, checked my plugs, and within 10 minutes it quit, and ran fine, no more codes. Then i got the nelson tune, and noticed a major difference in the way my truck performed. But as for running catless, u do notice a difference in the smell of ur exhaust, thats normal.