[foggy e90]

when driving normally I get a sudden loss of power the car seems to die for a split second then kicks back in. There seems to be no consistancy to it and will happen at any time, any gear and any revs, took it to my local mechanic ex BMW he said it was the coils, two showed up faulty on diagnostic so were changed now it is happening more and more no fault lights are showing. and I appear to be getting a lot of carbon biuld up around the exhaust tips. to me it feels like fuel starvation. Can anyone help.

[A_P]

Next port of call would be looking at injectors, rail and fuel pump.

Is there any leakage of fuel? The 330 is notorious for breather pipe.

[A_P]

was the car stuttering before you changed the coils? Which cylinders?

[RichJ]

Could be the HPFP?

[djgandy]

Originally Posted by RichJ

Could be the HPFP?

Maybe, is it an 07-ish onwards (N53) engine?

[MrPogle]

Mine did exactly the same. Once they fixed the coils it got worse. When they replaced the HPFP and injectors, all sorted.

[chrismanchr]

if its n52 or pre march 07 it could be vanos soleniods ,theyre about 50quid each and easy to replace or take out your existing soleniods and swap them round(theyre exactly the same)

vanos soleniods can cause alot of issues including loss of power and poor running and doesnt allways put up an engine light ,very common issue on n52 engines

[foggy e90]

Originally Posted by A_P

was the car stuttering before you changed the coils? Which cylinders?

It was stuttering but very rarely, Did have problems with the coils before though but light never stayed on long enough to ascertain which were the problem

[foggy e90]

coils 2 and 4

[foggy e90]

Originally Posted by MrPogle

Mine did exactly the same. Once they fixed the coils it got worse. When they replaced the HPFP and injectors, all sorted.

What sort of price are we looking at ?????? did you change all the coils

[Jay2301]

N53 engines have had "product enhancement" recalls on the injectors last year so if you haven't already had them checked/changed you should get that for free..

If its a HPFP problem which it sounds like to me from personal experience it can be very costly... I argued with BMW it was a known common fault and I shouldn't have to pay the lot. After checking I had a good amount of main dealer history they agreed to pay for the part and I payed th3 labour.
Think the part was about £300 and labour around he same.

Are you getting any long cranks on start up? If so it's pretty much nailed on HPFP failure IMO.

[foggy e90]

Originally Posted by Jay2301

N53 engines have had "product enhancement" recalls on the injectors last year so if you haven't already had them checked/changed you should get that for free..

If its a HPFP problem which it sounds like to me from personal experience it can be very costly... I argued with BMW it was a known common fault and I shouldn't have to pay the lot. After checking I had a good amount of main dealer history they agreed to pay for the part and I payed th3 labour.
Think the part was about £300 and labour around he same.

Are you getting any long cranks on start up? If so it's pretty much nailed on HPFP failure IMO.

thanks for that will look into into this