Hey all, I'm wondering why Im having o2 sensor burnouts this is the third one in the same number of years

Question

Make of car VW Jetta GLS
140 000 kms
I had two burn out on me in the last 3 years ......I think it's going again. same symtoms. It's a real pain and costs a bunch. It seems to be ok now but I know it's going the light went out and I'm not smelling the fumes but I know it's just a matter of time before it blows again. I did put a bit too much oil in the other day. Maybe it was just too full. I tend to burn about a quart every 2000 k or so maybe less I'm not sure.......thanks

Answer 1

Things that usually kill o2 sensors are lead, other metallic octane boosters and losing their power when the engine is running.

The last one is puzzling to me - but I know that if 4/5 wire sensors lose their power connector when in hot exhaust fume, they tend to die VERY quickly.

As for you burning huge amounts of oil, try NOT overfilling - if the oil is being burnt, then yes, this amount may contaminate the sensor - though surprised it is actually killing it.

If you are using a pint of oil per 1000 km (600 miles) you might need to look at what else is happening with your car.

Also, try googling for generic replacement sensors - they can be VASTLY cheaper than brand name ones - and going on how you get through them, it is hard to see how a cheap one could last any less!

Mark

Answer 2

O2 sensors do wear out but you need to consider:
1.)Are you purchasing aftermarket sensors? Construction may not be as QUALITY built as original manufacturer's parts. 2.) The engine may not be tuned properly or have mechanical problems that contribute to poor emissions. 3.) You may have contaminated fuel 4.) Are the correct tools being used to replace the sensor and is it TORQUED properly? It could be damaged from the way it is installed. 4.) The Catalytic Converter may be the root problem. Restricting the exhaust flow can cause too much back-pressure (same thing with the muffler).
If you are BURNING oil at a rate of 1 quart per 2000K .....
THIS IS THE MAIN PROBLEM!!!!! Residue can build up in the combustion chamber, exhaust manifold, exhaust pipes, Catalytic Converter, muffler, and the rest of the exhaust. Exhaust temperature must be within a minimum and maximum range. When oil is introduced to the combustion process, this changes everything. You may want to seriously think about another vehicle. Engine repairs on high mileage engines WILL BE EXPENSIVE!

Answer 3

Any car with high mileage burns up o2 sensors for some reason, it is a waste of time and effort to try to find out why.The good part is that you know when it is going and can decide if you want to throw more money into the car or dump it.
Good luck

Answer 4

A bad cat will cause premature o2 sensor burnout. Get a new cat.

Answer 5

Might want to have (catalitic converter looked at could be clogged). 2 plugs might be fouled or improperly gapped.and make sure air filter is not clogged.