Bank 2 Ltrim +25

[67SS509]

Been tuning on a 408 this week. Dialed in the VE table then the MAF. AFR's are 12.8 at WOT and the l-trims 0 out. Problem is that when it sits and idles (in closed loop) the bank 2 l-trims climbs to +25 while bank 1 stays about -1 to -2. With the wide band on bank 2 it shows the afr dropping to 13.1-13.2 which says the pcm is actually adding fuel. Put a new sensor in and it did the same thing. Voltage from the O2 sensor is low so it's seeing a lean condition but the pcm is trying to add fuel. Anybody got an idea what is going on?

[jfpilla]

Vacuum leak or header leak on that side?

[67SS509]

I thought about that too but if it was a leak of some kind then the wideband would also show it as lean. I have double checked for leaks also.

[67SS509]

Turns out the new sensor was bad too. Replaced it :bash: with another new one and now everything is dead nuts.