PEAKE R5/FCX-II Code "0A" says...

[1000_eyez]

Emission (lambda) control. The "0A" code is the fault code that comes up on my 89 535i 5-speed. The car runs and drives fine. Been driving it for a week now since I put a used ECU from a 89 737. It actually seems to run and drive better than the remanufactured one that was in when I bought the car. That ECU fault list came up "--" no faults. I don't have the remanufactured ECU anymore...ruined by me. Anyways, I'm new to BMW's and could use some help...anyone know?

[myles]

You get that when the O2 sensor is telling the ECU that it is running too lean or too rich for too long.

I had the same problem on my car and the fault was with the O2 sensor. It was telling the ECU that the car was running too lean, so the ECU kept making it more and more rich. It fouled the plugs and ran like crap.

But since your car is running OK, so you might find the problem is elsewhere. Possibly a vacuum leak?

[shogun]

I had the same some weeks ago, and funny, both on my V12 engine should be defect.
Finally I found out that it was an old stored fault.
Made a reset/deleted the faults, drove the car around the block, tested again and no fault anymore.

Note that when you make a reset, that before you test the car again, drive for s short while or let the car come to normal operation temperature.

The oxy sensors measured values are overridden during the first 90 seconds or so by the ECU which works with a nominal value till the cats are heated up.

[1000_eyez]

Thanks for the help. I'll let you know what happens. It'll have to wait till I get home later.

I had the same some weeks ago, and funny, both on my V12 engine should be defect.
Finally I found out that it was an old stored fault.
Made a reset/deleted the faults, drove the car around the block, tested again and no fault anymore.

Note that when you make a reset, that before you test the car again, drive for s short while or let the car come to normal operation temperature.

The oxy sensors measured values are overridden during the first 90 seconds or so by the ECU which works with a nominal value till the cats are heated up.

[Incantation]

nice ride man.. looks awesome

[shogun]

Diagnostic procedures & Frequently Asked Questions https://secure.lambdapower.co.uk/dia...c_index.asp#q3