REx injector and O2 sensor failure after 10,000 miles

[sjjhr]

I have a 5 yr old Rex with 50,000 miles.

Maybe 10,000 or less of that has been done with the REx.

BMW now say it needs:

-new injectors
-O2 sensor
-software update.

£1,000

Injectors failing on a car, especially a BMW, with 10,000 miles?

And then, maybe masking underlying faults with the HV system as those error codes won't clear until the above is sorted out.

This is the most unreliable car, and most unhelpful car company, I have ever had the misfortune to deal with.

Anyone else had this?

Thanks.

 

[TheMK]

I'm sorry to hear about this. 1000 pounds is about US$1350, an expensive bill to pay for sure!

And then, maybe masking underlying faults with the HV system as those error codes won't clear until the above is sorted out.

If you read the faults through ISTA (BMW's dealership diagnostics system), it will show those faults, as well as any additional faults that may arise. No need to worry there.


I can see why the injectors might need to be replaced, though it is certainly a bit premature I think. With the REx, as it is used so infrequently old petrol will sit in the injectors, without clearing through very often. In my snowblower, with has a carburetor, I forgot to drain the carburetor before storage one year. When I pulled it out ~6mos later, the gasoline (which has 10% ethanol), had clogged it all up, and I had to rebuild the carburetor. Now, not only do I use ethanol free in my snowblower, I also make sure I drain the carburetor. I would expect that infrequent use, with gasoline just sitting in the injectors would lead to reduced lifespan. Now, reduce lifespan meaning 10,000mi seems a bit excessive. You could ask the dealer to read how much time was used on the REx, using ISTA.

It seems like every time they fix a REx problem, they want to do a software update. I'm not sure why, but that seems to be what happens.

 

[PBNB]

It seems to be a common theme with the REX. It is supposed to be a backup but if it is used more often that can help move things along.

You state that you have been using the REX about 20% of the time. That is a lot more activity than what I have seen on ours where we are about 3% usage.

It sounds like you use the REX quite often so the failure of the injectors is strange. The O2 sensor could go at anytime but like TheMK said, one code may contribute to another so if the O2 sensor is not reading the gases properly, the ECU could point to the injectors as the cause. Or the other way around.

Was the REX running like crap when you took it to BMW? Or did they find these issues when they scanned it?

Perhaps you got some gas with water in it?

 

[TheMK]

It's definitely possible that if the injectors are bad, that the air fuel ratio is running too lean, or too rich, possibly swinging between conditions, causing the Oxygen sensors to be labeled as faulty by the RDME.

 

[jadnashuanh]

IF the REx will start, I'd consider dumping some injector cleaner in the tank and see if that helps things out. IF they say they need to be replaced, it probably wouldn't make the problem worse.

Does England add ethanol to their gasoline? Thought that was mainly a US (and Brazilian) thing. Ethanol can tend to gell the gasoline over time, and it can also affect the octane level (dropping).