So at idle, 646 rpm, your Bank 2 STFT is +12.5 and the LTFT is +19.5. This tells us that the ECM is adding fuel in Bank 2 to maintain a stoichiometric Air-Fuel Ratio (AFR), which is the ratio of air to fuel that burns all the fuel with no excess air. High positive fuel trims typically indicate that unmetered air is entering the Bank 2 intake without being measured by the Mass Air Flow Sensor.

A few things can affect Bank 2 with a lesser or no effect on Bank 1. For example, air leaks at the Variable Valve Timing solenoid gasket or oil filler cap gasket. If oil is seeping around those gaskets, air can be sucked in. Another common culprit is the part-load breather hose that can develop cracks.

One other helpful test you could do is to show us the same screen as above but with the engine at 1,500 rpm and 2,500 rpm.

Cheers,

Don

 

Don B, Thank you so much. You are amazing! And wonderfully quick to respond.

So here is the big question: Which of the gaskets and hose you mentioned could have been knock askew by a transmission rebuild, if any? This code came after the tranny was rebuilt this month?

Either way, where would would I find the part-load breather hose and the vvtiming solenoid gasket? Oil filter gasket I assume if where the filter fits ino the engine. Or am I wrong?

 

Hi Len,

I think the most likely component to be damaged during a transmission rebuild would be the part load breather hose. The hose runs from the front upper edge of the left camshaft cover, under the intake manifold and throttle body, to a connection at the firewall. During the transmission removal process, the transmission mount is removed and the transmission and engine are allowed to tilt for access to the upper bellhousing bolts. This could strain the part-load breather hose or bring it into contact with the firewall or some other component. The plastic becomes brittle with age and is easily cracked. Because of limited access to the hose due to its routing under the intake manifold, the easiest way to test it is with a smoke machine attached to the forward end of the hose. It is Part 2 in the diagram below, which shows the engine from the rear looking forward with the upper intake manifold removed:


The VVT solenoid gasket is near the front of the camshaft cover. It is Part 9 in the diagram below, and it can be easily changed without removing the cam cover or solenoid. The oil filler cap gasket is a large O-ring on the cap itself, Part 10 in this same diagram:


Cheers,

Don

 

I'll let you know how it turns out. I will be away and wont get to this right away, but hope to have it concluded in October. Your notes and diagrams are wonderful and invaluable. Thanks again Len