BMW Questions? Ask a BMW Repair Expert for Answers.
What type of BMW do you have?
2738 Catalytic converter conversion, bank 1
273D Catalytic converter conversion, bank 2
Those faults are indicating that the catalytic converters require replacement. Seeing how they both have failed you had something else failed that ruined the cats. It could have been one of the components you already replaced.
You will need to put the car back to oem, replace the cats and see if any new faults come up and if they do fix the issue immediately.
I would put the oem intake back on, Ok good about the oem parts.
It could of
Yes they will need to be replaced and they will be expensive.
I would recommend oem parts, I would be skeptical about used parts though.
If it comes with a warranty then I would go for it.
Sounds like a good donor car, and no you would not need to replace the O2 sensors you can reuse them
That is the best diagnosis I can give over a keyboard. To be 100 percent sure you will need to bring it to the dealer and let them get there hands on it.
That is a back pressure test. Excessive back pressure indicates failed cats.
Yes you have, that is what is causing the poor performance. It sounds like a cat.
Yes that is a lot of backpressure Less than 2 psi.
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