Bank 2 lean at idle and cruise
This car is a problem car from another shop. They changed the purge valve, valve cover gaskets, all 4 02s, and mas air flow. When I looked at fuel pressure, it 5 psi before spec and would bleed off immediately.
I changed fuel pump, fuel trims are better at 20% versus 30%. I installed a new original mas air flow sensor, but same. Bank 1 is perfect only bank 2 is the problem. I even swapped injectors with bank 1 but problem remains on bank 2. I smoke tested the intake, no leaks.
What other tests can I do? I tested alcohol content which is at 10%.
I checked relative compression using a scope and that checked out okay the car idle is fine drives fine starts up fine there are no misfires. Forgot to mention the customer changed the plugs already.
Do you have a gas analyzer to verify fuel trim activity? If you reset trims back to 0 does the vehicle run poorly.
When I reset, car runs fine. No gas analyzer.
Are the o2s the other shop put in quality ones? I would also want to verify o2 operation with a scope, just to be sure you are not dealing with a PCM issue. I agree with the check exhaust for leaks, smoke test your exhaust system. Any TSBs on this problem?
Check the exhaust for leaks, very small ones, anywhere in the vicinity of the O2 sensors.
Can you post a pic of all 4 02 sensor graphs at idle and off idle? These were bad for little exhaust leaks. Also need to check timing and carbon buildup.
After reading everything that has been done I would check cam timing and compare it to the other side. That is provided you have a scope, a pressure transducer would be a plus.
I agree with Andy and James, exhaust leaks are big on these. Have seen quite a few leaks around oxygen sensor bosses.
I agree to look at o2 bosses. But for the future, anything like maf sensor and alcohol will affect both banks evenly.
One of the bank 2 injectors was leaking externally. Thanks everyone for the help. I think when I swapped injectors, I may have damaged it. Found problem after I drove the vehicle enough for the fuel to pour out.