BigJls1

Two weeks ago I gutted my cats and even took the time to put a piece of pipe inside (looks like a cat but is really just straight pipe inside). everything else is just as factory.

car sounds awesome and "feels" like it has more power.

98 trans am bone stock.

I drive alot on the freeway and use to get around 18 to 20 mpg

now it so bad it like 130 miles per tank.

car smells rich at idle bad, I thought that guttin them would cause it to run leaner.

also drove it for like 4 days before the ses light came on.

kmracer

iTrader: (1)

do you have a sim in place of the second o2 sensor?

BigJls1

no.

also put it on the lift this afternoon, noticeded three things:
1. I might have a very very small exhaust leak at the collecter on driver side. Could this be triggering false knock.
2. One pipe needs a little "clearance" help as it is banging the floor board sometimes , could this be triggering the knock sensors to retard timming ??

3. when I pulled the front 02 sensor on the passenger side
I kinda twisted the housing of the sensor and the wires and may have f**ked it up. I will replace it. I did not pull any other 02's.

Can just unhook the back ones and swap it with one of them to "test" to see if the aforementioned o2 is bad ????

Eurospec2

iTrader: (2)

If you have an exhaust leak anywhere near the front 02 sensor, the Sensor will read the extra air as a lean condition and cause it to dump fuel to try and correct it.

What do your fuel trims say?

BigJls1

thanks for the input. I currently have no wat to get a read out on the car....but this mod is the begining of the end of a stock vehicle as the next step is sts, 60#, and vavle springs.

this problem has sparked my need to get something to alow me to tune and diagnose my situation.

Eurospec2

iTrader: (2)

Give me a call, we can set you a good deal on a EFI LIve tuning suite and wideband combo

BigJls1

hmmm. This last tank is at 130 miles and Im just at half a tank.

does the computer need some time to figure out the new flow.

01'WS6

I'd change out your front o2's if your in doubt about their quality and tune out COT and tune out your error codes. Without having o2 sims or any kind of tuning then your car is running highly rich by gutting the cats.

BigJls1

Thanks.

new 02's should be installed tues morn.