[NFS]

I've been looking on the forum for some technical information on the problems that many 335i's have suffered with:

High pressure fuel pump failures
Injector failures
Coil pack failures
Carbon build up

I'm just curious about what is going on. Is this due to faulty parts, a more fundamental issue with direct injection or the quality of fuel?

My car has already had a replacement high pressure fuel pump, 6 new injectors and replacement O2 sensors. I'm not even sure that these parts are anything to do with the very minor problem I went to the dealer with, but BMW seemed intent on replacing anything that looked 'suspect'.

I would just like to better understand what's going wrong with these parts and why?

[zltm089]

Not sure why its so common with the 335i? What is different with the other e9x engines?

[Arch Stanton]

i'm furious with my local dealer. before the warranty expired it went in for a few minor issues and the turbo wastegare rattle. Turbos replaced which i expected then they also replaced HPFP and all injectors. ^weeks after warranty and engine management light comes on again and they replace all injectors again but this time reset the fueling (some injectors running rich, some lean). The bit I'm annoyed about is having to pay the excess on the insured warranty for an issue I maintain is the original problem they didnt sort first time out. Not explanation given as to why the replacement injectors failed in under 3k miles!!

[briers]

Originally Posted by Arch Stanton

i'm furious with my local dealer. before the warranty expired it went in for a few minor issues and the turbo wastegare rattle. Turbos replaced which i expected then they also replaced HPFP and all injectors. ^weeks after warranty and engine management light comes on again and they replace all injectors again but this time reset the fueling (some injectors running rich, some lean). The bit I'm annoyed about is having to pay the excess on the insured warranty for an issue I maintain is the original problem they didnt sort first time out. Not explanation given as to why the replacement injectors failed in under 3k miles!!

Surely those injectors were covered under their own 12 months parts warranty supplied by the dealer?

[E92westy]

Not the same car I agree, but similar issues.
I posted a question about my 320i on a non-car related forum and recieved a PM from a BMW main dealer aftersales manager..

"These issues with the engine management system are a big problem and very well known to all dealers and BMW UK.................. <snip>

The current crop (built within last 5 years) of petrol models both 4 and 6 cylinder as you have found out can suffer repeat problems with coils/plugs/injectors/o2 sensors/high pressure pump and sensors.......<snip>

...the dealer will try and switch you into something else and if they do and you are willing to try another then be sure to get a diesel... <snip>"

I firmly believe that it's a software problem, although I have been told by a BMW tech since (who was test driving my car) that new injectors have a different part number to the old ones...

I'm currently negotiating a switch into a diesel.

[zltm089]

damn, this is bigger than i though!!!...

[kdiz]

i didnt realise it was this serious, jeez. i might actually stay away from buying the 335i, unless bmw fix the issues before early next year

[M3-FAST]

My 325i vert had to have a HPFP within weeks of ownership, and was on its second or third set of injectors and coil packs in it's first 2 years - I lost count in the end on how many it had. Some were replaced due to poor running, others done as a recall when the car was actually running OK!

[creepy coupe]

Extended warranty is a must on these engines, anyone who forgoes it is a bit short sighted IMO I’m not saying it’s right, but the way it is.

[NFS]

Originally Posted by TrackRat

NFS-

There is a sticky and many threads on the HPFP failures that generally also end up causing related failures of the sparkplugs, injectors and coil packs. Turbo and wastegate failures and rattling are also common.

Thanks for that, very useful.

So unfortunately no-one seems to know why these failures are occuring?