O2 sensor replacement?

[Maranello]

Hi all, I was planning to sell my Z4 but I can't sell
It with the engine management light on.... it was plugged in a while ago and raised the O2 sensor failiure issue.
Can anyone recommend someone who can fix this problem and how much could I look at paying?
Many thanks!

 

[Scooba_Steve]

Assuming pre cat as they are the ones that tend to go, you can buy bosch for c.£90-100. OE sensors are usually double. You will need to know which sensor, not a hard job any mechanic should be able to do it, with tools they are a simple DIY. Post cat is more expensive as the exhaust has to come off.

 

[Ducklakeview]

As Steve says, probably pre-cat - I've used these a few times now and not had a single problem/failure.. https://www.ebay.co.uk/itm/BMW-Z4-E85-3-0-2003-BANK-1-4-WIRE-FRONT-LAMBDA-OXYGEN-SENSOR-O2-EXHAUST-PROBE/252254705181?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

You do need the "special" socket for removal, as it has a cutout for the cables to prevent damage. However, it's an easy 10 mins job that can be done from under the bonnet. Front one is easy, rear requires a bit of jiggling and loosening the heat shield, but no biggie.

Socket is £13.49 @ Euro.. https://www.eurocarparts.com/ecp/p/tools/car-service-tools/socketry-and-drivers/specialised-socket-sets/?SEASX022&0&&gclid=Cj0KCQjw4eXPBRCtARIsADvOjY0gVvvqON2E4AreDVHtLZKtd72nrTt9QIoDo2ypYa7CNSFLHzFEiv0aAglbEALw_wcB

And looks like this;



Mike

 

[Paulr]

Run a cleaner through it first though, it may be doing it's job (it measures exhaust gases before the cat, which is then compared to exhaust coming out of the cat measured by the second sensor, if it is not within tolerance the light comes on) but the fuel is upsetting it. Supermarket fuel always makes my management light come on. Another tank of better quality fuel, or some fuel cleaner additive and it goes out within 100 miles or so. Unless it really is a knackered sensor of course.

 

[Scooba_Steve]

As Steve says, probably pre-cat - I've used these a few times now and not had a single problem/failure.. https://www.ebay.co.uk/itm/BMW-Z4-E85-3-0-2003-BANK-1-4-WIRE-FRONT-LAMBDA-OXYGEN-SENSOR-O2-EXHAUST-PROBE/252254705181?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

You do need the "special" socket for removal, as it has a cutout for the cables to prevent damage. However, it's an easy 10 mins job that can be done from under the bonnet. Front one is easy, rear requires a bit of jiggling and loosening the heat shield, but no biggie.


Mike

Sorry, forgot the socket. For £25 those are worth a pop. I took the bracket off and didn't put it back, stupid PITA.