shep28

iTrader: (4)

My bank 2 ltft and stft #s look crazy- they go as low as -20 at idle and part throttle, but are closer to zero at wot. My bank one numbers look good- stay between -4 and 0. The two banks should not vary that much at idle and part throttle.

Recently, I cleaned my sensors and had the valve covers off due to a valve springs, seals, pushrods and cam swap. I checked the egr gaskets and they are not leaking.

I added +3.5 PE after the cam swap because I looked lean at wot and I would rather be safe than sorry while I wait for my pcm dyno tune.

What could cause this situation?

Taphee6

iTrader: (2)

Could be a leak in the header gasket...

P Mack

iTrader: (6)

How did you clean your sensors? Did your problem start then? I would try swapping the o2 sensors left to right and see if the ltrims change too. You're fuel trims will go to zero at wot if they are always negative so don't worry about that.

shep28

iTrader: (4)

[QUOTE=P Mack]How did you clean your sensors?
scrubbed carbon/soot off with a rag soaked in parts cleaner. light sand with 1200 grit sandpaper.

Did your problem start then?
I had a rocker arm bolt break on ex. cyl. # 1. After I fixed that I took off all the rocker arm bolts and reinstalled them all to spec. I cleaned the o2 sensors at this time as well.

Cheatin' Chad

iTrader: (3)

I used a propane torch to clean my o2 sensors. It worked great and they have been functioning as well as before for over 2k miles. I am changing them out for Denso O2s when I get off my lazy butt.

shep28

iTrader: (4)

[QUOTE=Cheatin' Chad]I used a propane torch to clean my o2 sensors. It worked great and they have been functioning as well as before for over 2k miles.


I will try that.