For the 02, the Ω reading (presuming you mean for the heater) will also be very hard to get an accurate reading because they are very low resistance on the order of an ohm.

I've found that if I'm getting heater errors I've been able to reset the DME O2 calibration by unplugging the O2 for two engine starts and plug them back in.

At the age of your car if the parts are original it's overdue for replacing all.

Use OE or OEM only for MAF or for O2 (at least for pre cat sensors)


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2011 E70 • N55 (me)
2012 E70 • N63 (wife)