JTKompressor

My generic reader shows a PO131, O2,low voltage, bank 1, sensor 1 Fault. I've remover the O2 sensor before the cat., cleaned the connectors, put it back and the code returrned. It appears it could be a multitude of causes in addition to the MAF which I removed and cleaned 2000 miles ago. That fault (PO101) has not returned. Has anyone been lucky enough to just change the O2 sensor and fix this fault?

wvadam

How many miles are on the car? I just replace that sensor on my car at 170k km or ~100k miles. If your car is close to this mileage you should deffinately change the sensor. There is a substrate material inside which wears out over time and it can no longer provide enough feedback.

JTKompressor

The car only has 53,000, I'm the original owner and it's never been out in inclement weather.

Glyn M Ruck

O2 sensors have a design life of about 80,000 miles before they cycle too slowly. They can also be poisened by the car ingesting silicone from silicone sprays etc which should never be used under hood.

I suggest you replace the sensor. Please only use genuine OE heated sensors - No generics even if they are Bosch. They don't work. This does not mean you have to buy from a dealer but from a reputable Benz Spares outlet.

JLD2k3

Glyn, why don't the generics work? My BMW mechanic buddy (who helps me with my MB frequently) told me there's no difference between the various O2 sensors as long as they are heated and that the extra money (assuming it's still Bosch) is just for the length of cable and plug. What's the deal?

Glyn M Ruck

Yes - you have answered one of the questions already. Many of the Bosch generics are not heated. That said I know a number of people that have bought Bosch heated generics to save money & converted them to the Benz plug only to throw codes & have all sorts of crap.

I think that while in principle all O2 sensors operate the same way the Benz sensors have specifically profiled cycle times etc. and the Benz electronics are matched to this.

When Bosch makes a generic they have to broaden it's specs so that one size fits all - so to speak. You might well find that fuel trim & all is just fine with the generics but that they upset the diagnostics. Like changing the current draw of a headlight bulb does.

So having experienced trouble I always recommend against generics. In this country if you stay away from the dealers & buy the correct sensors direct from Bosch - there is virtually no price difference between the genuine article & a generic.

wvadam

not worth risking it on universal o2 sensors. I went that route with my last car only to find that a few months later water leaked into the wiring and ruined it. Its not a lot of money extra to pay for something that is guaranteed to work perfectly and it saves you the labor of splicing and soldering wires and risking a failure.