[Stu123]

So i have problem with my 2008 325i n53, when the car is left overnight or for any long period of time it takes about 4-6 seconds to turn over and start, rarely it will start and be fine but frequently it will start with a misfire and will go after the car is turned on and off. Occasionally when this happens it will be alot worse and the engine will start but run at about 300/400 rpm and shake like crazy and sound almost like its not even running. From doing a bit of research i am looking towards injectors but dont want to be forking out 1000+ for it to not be. Any ideas of what could be causing this problem.

The car was plugged into diagnostic not long ago as water pump had failed i believe the 3 Fault codes were

High fuel pressure
Injection cut off
Nitrous oxide sensor

Very frustrating and would like to get to the bottom of it,
Just to clarify car runs perfectly when its warm.

Thanks in advance

[Slev706]

I have recently had this same sorta problem with mine, started of subtle. Now its grim to drive (no power, smoke) it was a bitter pill to swallow but it turns its a leaky injector. I am awaiting the part and off to the garage i go and i hope this will address the issue, i have read people just changing plugs and coils but this only pros-pons the inevitable.. bust injector(s) i hope you get sorted! Ill update in the next couple of days with my new injector.

Ps... i believe higher octane fuel is better as it burns hotter, burning deposits left on your plugs away better, pull your coils out, have a look for oil/fuel mix on the rubber shrouds.

[Stu123]

Thanks for reply, the car has had a new set of plugs about 5000 miles ago, as for coils it has had one replaced whilst owning it, started out as very occasional blip to all of a sudden going. I do think im starting to get another one on the way as i am getting a very occasional blip when accelerating low down the rpm. But this problem i have had is like you said it started off as a slight problem and has got alot worse overtime but car is still running perfectly when hot or when it starts after not being left for 8+ hours. As for injectors im under the impression that each bank needs doing at the same time because we cant rum diffrent index on same bank?��*♂️ Just kind of praying i can fix without having to fork out on injectors.

[Slev706]

Hi again mate, go on euro car parts and enter your reg, theres a sale on, i bought one injector it came today and its the correct injector for cylinder 3 (the spark plug housing filling with fuel) cylinder 124 fine and dry. Dont panic, go to a garage and ask for a special additive to clean your injectors (redex but better apparently) then use hi grade fuel (vpower) change all plugs when changing spark plugs. Recent change or not. Your coils should be fine, check for smell and burning around where wiring enters the coil. Injectors are can be pricy but the labour shouldnt be. Any competent person can do this (correct tools always needed) hopefully get my 320i back tomorrow/friday. Will keep you posted
Good luck

[Stu123]

Coil pack died on me today, well i beleive so anyway, timing or what haha, will know tomorrow. Fingers crossed that this could of been linked to my starting problem but i doubt it...

[Slev706]

I hope that is all it is! I had a call today, injector 4 needs replacing, sale still on at euro so ordered that today as the the 1st one i ordered was correct fitment so thats good. Hes replaced all coils and plugs oil, filters and serviced ac, awaiting injector tomorrow. Have you ran any superior fuel since the last post?

[Slev706]

All 4injectors replaced, coils plugs, all filters and overall a good service! Car is back to full health as i only bought mine a couple of weeks ago and the last owner had neglected it for a little while. Hope you got sorted to.