osuhunter07

iTrader: (10)

Hey So the basic mods are in my sig, but the fuel system is brand new 42# injectors anda 255. Once the engine bay gets warm which takes for ever, headerws are 1 7/8 stepped to 2" witha 3 1/2" Y pipe. After about 30-40 min of driving the car will start bucking real bad. I did a lot of searching and here is what I came up with

Coolant Temp- ATAP reads 171 mostly
Misfires- None
Plugs-New changed again, pusling got less, but not fixed
02's- bank 2 reads 450ish but when bucking happens goes to maybe 200-300 even 100
bank 1 reads anywhere between 200-700 (exhaust leak?)

injector pulse. I think this is it, when it is bucking bank 2 will be at like 10, bank one is around 3-4. The plugs on bank 1 where pretty white, looking pretty lean. could the 02 be bad? why does it only do this once the car gets really warm?

Any help is really appeciated, I am trying everything. Thanks!

Bombguy99z28

Well, since you say its when the car is warm, that would probably mean your problem is related to closed loop (when the car has reached normal operating temps but not above a certain TPS). Your O2s should bounce up and down from really low (50-100) to really high (800/900), not always to those extremes but thats a general idea. If the O2s don't correctly oscilate, then the car won't function very well in closed loop cause it doesn't have enough data to make accurate corrections, essentially thinking the car is always rich or lean, usually if you have an o2 stuck real low it thinks its always lean and dumps a ton of fuel, in my experience sometimes even stalling the car . Usually this will result in the 'insufficient switching' SES light though.

I would recommend checking the O2s, maybe switching them from bank to bank and see if the bad data follows the O2. Maybe if a fellow f-body friend can let you borrow his set, see if that helps instead of just buying stuff without knowing for sure if it will fix the problem.

osuhunter07

iTrader: (10)

Thanks man, so basically it is down the the 02's not really reading right and the car not hving enough info to run right. could this also be because of an exhaust leak before the 02?

DramaFoYoMama

It could indeed be from a fake lean condition caused by a leak. I would venture to guess that it would be on the passenger side, since the duty cycle on that jumps to 10%. To get an idea, what RPM and TPS are you at?

osuhunter07

iTrader: (10)

any rpm, but once i give it over maybe 30% gas it will be fine. Also I looked at the plugs, passenger side are black, drivers are white.

DramaFoYoMama

Is your motor segregated? That's pretty consistent with what I said. There's a false lean condition on your passenger side from either an intake or exhaust leak. It's dumping in extra fuel, but your motor doesn't need it. It's showing as carbon deposits on your plugs. Get to diggin'!

osuhunter07

iTrader: (10)

Thanks man!