1978transam

My check engine light keeps coming on with the codes P0137 and P0157. I have already changed out the two front O2 sensors because before this error it was telling me that the front two O2 sensors were bad. Don't know why it is giving me this error? Has this happened to anyone else? Thanks.

teke184

iTrader: (5)

hows the wiring on the sensors?

did you clear the codes after doing the sensors?

Unertl42

iTrader: (63)

I'm pretty sure those codes are for the the rear o2 sensors. Do you have headers?

1978transam

I do not have headers and I have cleared the codes before. The codes keep coming back.

hj99Z

iTrader: (1)

Try replacing the rear O2's

SlowSS416

iTrader: (3)

o2s are the most problem causing part ever on these cars. Definately replace

FiredUpZ28

There are no codes that tell you 02 sensors are bad. It tells you that the circuit voltage is out of spec - high, low, slow to respond, and the heater circuit performance. Sounds like your running rich to me if the voltage is low. Why replace sensors that are doing their job? O2 sensors are the most misdiagnosed components I've seen. Usually its not the sensor itself unless it was killed off by running rich or misfiring. Same with cats.

P0137 - Heated Oxygen Sensor (HO2S) Circuit Low Voltage Bank 1 Sensor 2
P0157 - Heated Oxygen Sensor (HO2S) Circuit Low Voltage Bank 2 Sensor 2

Those are rear sensors.... do you have cats? Cat problems can cause 02 sensor voltages to vary too. Check your connections as well.

Edit: can we get some info on the car? Year, Make, Model, Engine, Mileage, Mods, recent maintenance, stuff like that.

1978transam

I have a 2000 WS6. The fuel pump has been replaced as well as the front two O2 sensors. Their is a pipe that a mechanic just rigged because he said that it had a hole in it and that was normal for these cars. Other then that the car is stock.

therealcreeper

iTrader: (37)

an exhaust pipe?

1978transam

No some pipe in the engine bay as far as I know.

hj99Z

iTrader: (1)

If you still have your old front sensors that you changed, which didn't fix your problem, try replacing your back sensors with the old ones just for grins. The codes you have point to the rear sensors, i don't know why your doing anything with the front ones . . .

therealcreeper

iTrader: (37)

interestinggg. wanna see if you can find it? i'm curious now.

camaroracer91

iTrader: (5)

i have that same codes would tuning them out help using a diablosport?

Dan Stewart

You have those codes because you no longer have rear o2's connected. At least, you shouldn't because there is no bung on that ORY that allows you to reinstall the rear o2's.

In short, yes, you need to tune those codes out.

As for the original poster, how many miles on this car?

therealcreeper

iTrader: (37)

a diablo can't really "tune out" codes. it can only clear them(unless the new on can as it has been rumored). this means that as soon as the computer runs it's checks the light'll come right back on.

camaroracer91

iTrader: (5)

so i need to go to a tuner cause i already did tune out the codes and my car runs fine but as soon as it comes on my car gets like a violent shake

FiredUpZ28

Tuning them out won't get rid of the shake. Rear O2s have nothing to do with changing fuel trims or anything driveability related. Just catalyst monitors.

camaroracer91

iTrader: (5)

then what would the shake be from cause it only happends when the engine light is on once the codes are tuned off the shake stops.

FiredUpZ28

are there any other codes maybe just pending? Most scanners should be able to see pending codes. The shaking could be since your on a basically stock tune (can't really do fuel trims properly with a Diablosport). And headers can make the car run a bit rich so, I dunno - its possible. Easier to have the car in front of me to help. Even better to have a scan tool on it

Dan Stewart

Did you extend the harness for the front o2's so you could hook them up?

Because the stock wiring will not reach back where they need to mount with longtubes.

If not, I'm willing to bet you have them hooked into the harnesses for the rear o2's.

If you did use an extension harness, make sure you didn't connect the left to the right and vice versa.