smoggist

Hey there,
I just got my blackbear tune the other day. After driving around for maybe 10min i got the damn CEL again pulled the codes and got p0134 and p0135.It must have recently come up because i scanned the codes right after the headers and just got the normal rear 02s missing. Is my drivers side front 02 fried? i couldn't get sensor activity as it was running on open loop. Rewire the rears for the front and give that a shot?

03 silverado

iTrader: (1)

i have the same problem after i installed headers, put new o2 sensers in an a week later same thing im just gonna get the codes shut off wit my tune

smoggist

I don't know if that's necessarily a good idea... just blocking the codes is kinda a band aid fix imo. Its running open loop now, not reading from the front sensors and im getting an excess of unburnt fuel with the exhaust. What codes were you getting?

Slammed96

iTrader: (5)

check that your sensors are getting good ground as well as power. I had a similar issue with mine that turned out to be the tune, but always good to check over everything to eliminate variables. Easy way to check if its the tune is just swap the old ECM back in an see if it will still pull the same code.

03 silverado

iTrader: (1)

im just gettin po135 an i no there reading cuz of EFI live log just something wit the tune is setting them off

smoggist

P0135 is the heater code I believe. The headers mustn't retain enough heat to keep the sensors happy. The trouble is i'm not even getting power to that sensor, hence the p0134 code.... Gonna go try to figure it out this evening yet.

smoggist

Well, still no hi. I swapped the sensor out for one of the rears and made sure the connections were good. i'm still getting the same codes. Beginning to wonder if it's in the tune? Might try going back to the factory tune

smoggist

I'm starting to get really pissed. I swapped sensors and i'm all getting the same p0134 and p0135 codes. put the factory pcm back in and i'm still getting them. Do any of you guys have any suggestions on what to try next? Thanks

1FastBrick

iTrader: (17)

If you swapped the rears and are still getting the code, and then swaped the pcm and still get the code. It's probably related to the header swap. These codes seem to be common with Header installations.

The rears not being used can cause the rear set to go bad. It's not the Tuners fault but he may be able to make an adjustment for you if you explain the problem you are having.

It's your responsibility to make sure the sensors are working properly and that there are no other Electronic issues with your truck.

rel3rd

iTrader: (42)

^^^^^^^^That is what you need to diagnose.

A P0134 code is not for voltage not going TO the sensor...it is for an issue with the voltage returning to the ECM.

The factory wiring diagram will tell you what wires are connected to that sensor and I'd start off with making sure the wires are not broken, or melted, or whatever, before doing anymore part swapping. The ECM swap pretty much eliminated the tune being at fault, so I'd be looking real hard at why there's no power to the sensor, which when found and repaired, will likely be what fixes the problem.

The P0134 is usually tripped with a P0154 with headers due to slow switching voltage, but a P0135 is pretty much telling you that there is a wiring and/or voltage issue in the wiring going to the oxygen sensor. You could also double check that no pins at the ECM to harness connection are bent over.

Good Luck. I'm sure you'll figure it out.