I installed my longtubes a few months ago with resonators. I installed the front O2 sensors, but my rears where both pretty much welded into place so I left them off. I have a tune from PHP to account for my cat delete, but just about a month ago I started to get a code for my bank 2 running lean. I was towing something at the time on my tow tune, so I switched back to the performance tune and cleared the code, but a few days later the code popped up again. Is the fact that I do not have my rear O2s causing this or is it something tune related?

 

No, its most likely a vacuum leak or even a possible small exhaust leak creating a false lean condition.

Thanks

 

I got a lean bank one code awile back turned out to be a bad o2 sensor. After installing a new o2 sensor code never came back. Hope this helps.

 

Ok, so I cleared that code and about a week later it popped up again. But this time it had another one...
P0174: System Too Lean (Bank 2)
P2196: O2 Sensor Signal Biased/Stuck rich - Bank 1/Sensor 1

So, what is going on here? My best guess at this point is an exhaust leak on the gaskets (I had reused the Ford factory ones), causing the system too lean code. Truck tried to compensate and started to actually run rich, causing the driver side O2 to go bad... Just want to get ideas before I go back under and start trying to fix things, not exactly the easiest to change the gasket for the passenger side header.

Also, if it makes a difference, I soldered in my own extensions for the front O2 sensors. I wouldn't say I did a poor job, but it was my first time soldering, so could that possibly be causing these issues?

 

See my response in the PHP forum. (I think the sensors are probably compromised.)

- Jack