kevsvette66

i had some problems with my two front oxygen sensors so i just moved the back ones to the front. and put simulators on the rear but since then my car has run very poorly. may this be due to the sensors..? are they all 4 the same or does the front differ from the back sensors..?

slow

iTrader: (7)

the f-cars the fronts and rears' are the same.

Ryan

Jake19_2

All four should be interchangeable, infact I just bought Rear 02's from a Vette to go on my f-body, Im placing those in the front.

BADBOYZ28

iTrader: (228)

That I know of they are interchangeable.....I'v done it several times with no problems. What is your car doing??

Viper

iTrader: (6)

I went to Lowes and bought a cheap propane torch; $15.

Put the O2 in a vice, hit all 4 sides for 2 minutes with the torch, and reused my O2's.

They came out sparkling clean.

Might be worth trying.

kevsvette66

I do not know what is really going on with my car.? bone stock i ran 13.3 best et. 1/4 mile. I just put 4.10 gears, all free mods, headman hedders, 2400 stall, tranny redone with corvette servo, blue cluthes, hypertech programmer, ported the throttle body, removed the screen on the mass air flow sensor, and know i seem to be running worse like 13.9 all night. i blamed the sensors so i put simulators in back and moved the back ones to the front.? any ideas on why running so bad..? thanks for ideas or suggestions.

zo6vetteman2003

iTrader: (1)

I think the ceramic could be cracked. There is a large difference in cost between front and rear O2's through GM, but I really don't know the reason exactly. I would go to Autozone, order 2 new fronts, and you should be good to go. Adding too much torque to the O2's cracks them. If you have a diagnostic tool, you can monitor the O2 sensor voltages to determine if they are good or bad. If the voltage from the O2's changes rapidly between .100mv and .900mv, this is considered normal. The simulators should put out a constant voltage of .450mv. If the voltage changes slowly in bank 1, or bank 2, or is defficient in covering the voltage range I've quoted, then one or both are most likely bad. A bad O2 sensor sometimes does not prompt the PCM to throw a code right away. The PCM will determine this over time, if the fuel mixture cannot be corrected, then defaults to a pre-programmed STFT and LTFT and throws the code too rich or too lean. It also is easy to go through O2 sensors like candy if the mixture is too rich. The rear O2 sensors basically mimic the front O2's votage outputs back to the PCM helping the PCM determine catalytic efficiency. If there is a constant wide disparity in voltage, it means that you may have a catalytic converter failure. This will show up as pressure during the evap air purge and throw a code. Simulators cause two things to happen with their perfect constant .450mv output. The PCM will lean out the A/F mixture because it thinks that the cats are performing very efficiently, so tuning is needed to make up for the +/-25% disparity in overall voltage range if more horsepower is desired. It also tells the PCM basically that the cats are installed.

technical

I vote the MAF screen messed you up. Get the car tuned. Unless there are DTC's pointing to something.

GT Griller

iTrader: (8)

Its the programmer as well. the HPP3 is useless with headers. They will tell u them selves that instead of helping it slows u down. Unprogram the car and i bet u will feel a difference. The programmer sucked on my car as well. Although it helped my friends stock TA 3 tenths. Oh and yea the MAF has something to do with it as well.