Engine Problem - HPFP, LPFP, Injectors...or something else?

[martins]

I doubt that plugs are the issue though. Best advice would be to extend that warranty.

You were right, it wasnt the plugs. I was taking the car to the dealer for some other warrenty things to be fixed and the missfire got so bad the engine warning light flashed - I think it was the first and possibly the last time I was glad to see that happen! Dealer read the engine codes and diagnosed faulty injectors and replaced all 6. All a bit lucky as the excess free warrenty ran out late December so it could only be claimed because the missfire had been experienced but not properly diagnosed then.

Meanwhile, they also found the gearbox oil seals were weaping oil, easy enough to fix except to get access you have to remove the exhaust and the catalyst retaining studs had rusted on. Solution? A whole new cat because they cant get the studs seperatly to the cat! Especially entertaining as the exhaust system isn't covered under the BMW used car warrenty, but they've had to honour it's replacement facilitate fixing the seals. All in all over £2000 of parts and labour

 

[metal licker]

I doubt that plugs are the issue though. Best advice would be to extend that warranty.

You were right, it wasnt the plugs. I was taking the car to the dealer for some other warrenty things to be fixed and the missfire got so bad the engine warning light flashed - I think it was the first and possibly the last time I was glad to see that happen! Dealer read the engine codes and diagnosed faulty injectors and replaced all 6. All a bit lucky as the excess free warrenty ran out late December so it could only be claimed because the missfire had been experienced but not properly diagnosed then.

Meanwhile, they also found the gearbox oil seals were weaping oil, easy enough to fix except to get access you have to remove the exhaust and the catalyst retaining studs had rusted on. Solution? A whole new cat because they cant get the studs seperatly to the cat! Especially entertaining as the exhaust system isn't covered under the BMW used car warrenty, but they've had to honour it's replacement facilitate fixing the seals. All in all over £2000 of parts and labour

Good result

 

[flybobbie]

So are these direct injection engines, seems like something to avoid!

 

[Z4M-2006]

The N series engines have been in various BMW's for approaching 10 years and in other cars since the late 90's

Injectors do fail, even on low pressure petrols..

Iirc you can get HP BMW injectors from around £125 recon now..

 

[R.E92]

Good result on the injector replacement and new cats!

I've always been of the belief that all cars break and it's best to save a little cash for when the worst happens but these N54 engines are in another league when it comes to failures so warranty is absolutely essential.

The exhaust system isn't covered but I'm pretty sure that the cats are an exception. I had mine replaced under warranty too, I think my injectors leaked so much fuel into them over a long period of time that they were toasted!