Warning Light Confusion???

[Beaver]

Hey,

I am new to this site so forgive with me if you have already answered this problem...
When I started my 330 Ci M Sport 2002 this evening after work a warning light came on. It was a yellow light with an engine illustration...i drove it home and it seemed to run fine. Can you tell me what the problems would be when that warning light goes on?

Thanks, Shane

[marti5]

Thats the CEL (check engine light) could be a number of things from your MAF to an o2 sensor, easiest way is to get a diagnostics done or you will start buying and fitting parts you don't need.

[Kai]

Originally Posted by marti5

Thats the CEL (check engine light) could be a number of things from your MAF to an o2 sensor, easiest way is to get a diagnostics done or you will start buying and fitting parts you don't need.

+1. With no other info than the CEL coming on you are pretty much left with those two options, and of the two diagnostics is obviously the best. Good luck, let us know what you find out.

[drz]

Here is a third vote for the suggestion above: have the codes read to help determine the cause of the CEL.

Did the light go away? Or is it there still?

[Beaver]

Thanks for your replies.

The light was still on this morning when I went to work, so I took it in to the mechanics to do diagnostics on it.

Result:

Code 228 O2 sensor (as you predicted)
Fuel trim bank 2 permissable range exceeded.

Recommendation:

The BMW mechanics said i have to replace all 4 sensors as they have no way of telling which of the 4 sensors are faulty.

Cost: $600 per sensor (ex Germany) + labour of approx $500

Wowwww, thats not cheap!!! the car warranty company will not be happy with me...oooops...im glad I got the warranty.

Thanks for your input guys.

[witeshark]

Wow, someone is gonna benefit from an extended 3rd party warranty. Cool.

[marti5]

Thats a load of bull a diagnaostics will come up with something like this " Bank 1 o2 sensor pre cat reached limits" or may say post cat which ever one it is, they are trying to rip you off thats for sure.

You would also get a different code number for the other bank, for all four sensors to go at once is billions to 1 ..

[drz]

Originally Posted by marti5

Thats a load of bull a diagnaostics will come up with something like this " Bank 1 o2 sensor pre cat reached limits" or may say post cat which ever one it is, they are trying to rip you off thats for sure.

You would also get a different code number for the other bank, for all four sensors to go at once is billions to 1 ..

I concur.

[Beaver]

they gave me the print out off the machine to show me. Too be honest, i have no idea what any of it means.

They said that it was probably just one failure, but the machine wont detect which of the 4 sensors it is, so they said that rather than spending hours and hours replacing one, then it not being the faulty one and so on and so on...they replace all 4.

[marti5]

Well Im not sure what diagnostic machine there using, but BMW GT1 machine would tell them which one, put a call out on here for anybody who has Carsoft diagnostics as this will tell you which one....

How they can say hours and hours to replace one of these???? you can even do it from above...

http://www.realoem.com/bmw/showparts...=11&fg=50&hl=8

[darkhorse737]

may i suggest you post what is written on the report or scan it, and someone here can decipher which of the sensors might be defective... if the print-out at all mentions that.

Alternatively, get a 2nd opinion from another shop ;-) their scanner might tell you which of the 4 sensors is/are defective.

then also, although this is not set in stone; BMW suggests you replace 02 sensors every 100,000miles(160,000kms)

[darkhorse737]

N.B. **

Strange for me(personally) because BMW Code 228 reads as: "System Bank2 too rich or too lean." If I was to trust that the code is accurate, that tells me the 02 sensors are indeed functioning, because it is able to read and register rich and lean.

IMHO, the dealers are taking the chance of replacing ALL 4 sensors in the hope of bringing the fuel trim within specs. And that to me is a 50/50 chance.

Either way, if your mech was "customer-friendly" readings being that only BANK 2 is the prob, they should have suggested replacing parts having to do with Bank 2(cylinders 4-6) only... 2 02 sensors, not all 4.

[marti5]

Originally Posted by darkhorse737

N.B. **


Either way, if your mech was "customer-friendly" readings being that only BANK 2 is the prob, they should have suggested replacing parts having to do with Bank 2(cylinders 4-6) only... 2 02 sensors, not all 4.

I agree, but what I find interesting is Ive only got common old Carsoft diagnostics and that will tell me if its pre or post cat sensor thats playing up and so will GT1 which is what BMW use so what are they up to is the question I ask myself......