So I'm starting a new thread for this because I guess it's time to dig deeper in this issue.
Symptoms: idle ok, might be slightly rough but really slightly. If the car is cold and you press the throttle slightly, it will be kind of stutter-ish. This situation happens also while driving under 2000 rpm. When the car is warm, there is no apparent loss of power and the problem seems at least attenuated if not gone.
- Multiple misfires and misfires on each cylinders: P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308
- P0040: O2 Sensor Signals Swapped Bank 1 Sensor 1/Bank 2 Sensor 1
- P1556: Fault at empty fuel tank/air injection sys
- P2097: Post Catalyst Fuel Trim System Too Rich Bank 1
- P2099: Post Catalyst Fuel Trim System Too Rich Bank 2
- P2177: System Too Lean Off Idle Bank 1
Note: these codes were not pulled together at the same time. The misfires are almost always here, the others take time to come. Yesterday, after the plugs change I only had P0300 to P0304. Today I had the rest of the P030X, and the P0040 and P2099 for the first time. Ther rest were pulled and cleared before.
What was done or checked: fresh service, spark plugs changed, dealership supposedly checked cats, vacuum leaks and fuel pumps, clutch. They put the problem on bad fuel quality (supposedly used by the previous owner) and average condition spark plugs, which obviously sounds like easy scapegoats and said it was not a big issue.
In my opinion and from my research it can be:
1. Faulty O2 sensors. Mostly the wide band ones (first ones) but it could be the 4 of them.
2. Catalytic converters (maybe they did not check it that well or at all).
3. Dirty injectors are not to be excluded but I don't really think it's the problem.
It seems very similar to the problem George has, Tubber had before. From the forum literature and Internet research, these 3 possible causes are the favored options.
If you guys have comments, experience or else, it would surely help me a lot.
I hope to solve my issue and post the results here so that potential future candidates for the same failure find their answer quick and easy