320d Injector Problems: Help & Repair Guide

I'm not sure if I'm in the right place, but the other forums I've tried have been pretty boring, and I haven't been able to get any answers there.
Or is this mostly VW/TDI vehicles? Maybe someone can recommend a good forum for me.

I have a 320D with 136 horsepower, a VP44 pump, and 115,000 kilometers on the clock. I'm experiencing various concerns/problems. Does anyone here know this engine well and can offer some 'advice and answers'?

- Specifically, I'm having problems with the oil pressure (the warning light takes 4 seconds to turn off after starting), which seems to be design-related.

- I suspect that the previous owner may not have taken good care of the machine. What testing options do I have? Should I replace the connecting rod bearings in any case? (Ingo from www.motorrevision.de recommends doing so for modern engines after around 150,000 km).
'How can I accurately assess the condition of the equipment? I've already considered sending an oil sample to a lab for analysis to check for metallic wear particles. (I work in a refinery.)'

- I'm experiencing - for me - strange noises. Specifically, when accelerating slowly (!!) in the first three gears (i.e., under light load), a dull, grinding noise gets louder/higher-pitched/more ringing... especially above 2000 RPM.

- This bright/rattling noise can be reproduced quite well when the speed (V) is constant, for example, in 2nd gear at a constant 2500 RPM. X is the accelerator pedal position at which V is constant. So... At position X: a constant, quiet noise, with hardly any diesel engine sound. At >X (slightly accelerating): a rattling noise. At >>X (accelerating more): the rattling disappears.
As someone who previously drove gasoline-powered cars, I'm very concerned about this noise that occurs within a very narrow range of the accelerator pedal position – specifically, right in that 'cruising' position, not below it and not above it. It seems like it's 'produced by the accelerator pedal itself.'
It sounds to me like it could be a PLEULAGER issue, or that something else in the engine is rattling/clattering at partial load... maybe it's just normal diesel engine noise.

- I've heard that Bosch recommends replacing the injectors at 100,000 km. I've also heard that the engines tend to become noisier after >100,000 km. And some people claim that replacing the injectors results in a noticeably 'smoother' engine running and a more pleasant sound.
Kennt sich da jemand aus? Injektoren kosten bei BMW ca. 325€/Stück = >1000 Euro zusammen.. Gibt es Alternativen? Jemand gab mir den Tipp Bosch könnte alte erneuern, dass wäre dann nicht so teuer.. ErfaSure, here is the translation of the text from German to English:

'Suggestions/tips?'


Thanks for any tips or advice. I want to keep this machine running for a long time. At the very least, I don't want to have to sell it in two years with a noticeable engine knocking or other major issues.

I've already tried using the search function here, but I haven't found satisfactory results.
Who can say what?

Hmm, I'm familiar with this engine, but I haven't seen anything like this before.

The engine is almost the same as a TDI, for example, an AFN with a variable geometry turbocharger and injectors.

As the nozzles age, the nail gradually wears away because the combustion process becomes less intense. Unfortunately, I can't quite imagine what the sound would be like.
But it is conceivable that...
1. Oil pump drive (chain).
2. Issues with the timing chain itself, such as a faulty or broken tensioner.
3. Pleu-lagershells
Otherwise, it's a very robust engine, except for the mass airflow sensor.
"I've owned BMWs for 4 years, and I've had 2 engine failures with the 320d models. In both cases, it turned out they had been running on gasoline instead of diesel, and we only realized it when the VEP (voltage early potential) started to corrode."
It would be best to have someone with some knowledge of the machine listen to it.

Also ich dachte die Motoren werden eher lauter.. dieses Diesel typische Rasseln, beim beschleunigen in kleinen Gängen bis kurz vorm Schalten.. Sounds like a truck.
do you understand?

The reason for this is the changes in the injection pattern caused by wear in the injectors. Therefore, Bosch recommends replacing them.

Unfortunately, I don't have anyone around who understands the subject matter this well. Even BMW itself seemed skeptical when I told them that the oil pressure only comes up after 3-4 seconds.

According to someone on the internet who works at MAN and is very knowledgeable about diesel engines/Bosch, and who drives a 320d: They have learned from inside sources that the symptoms are known. It's due to the oil filter being positioned very high and mounted upside down. Consequently, it runs empty if the engine is left standing for a while. That's my experience with BMW and this engine.

This guy also ordered new injectors instead of the old ones - and after the replacement engine didn't improve things. He told me that with the new injectors, the 'noise' that I was experiencing would be significantly reduced.

His technical explanations are easy to understand, and I think he didn't spread any misinformation.

jcee wrote:

Injektoren kosten bei BMW ca. 325€/Stück = >1000 Euro zusammen.. Gibt es Alternativen? Jemand gab mir den Tipp Bosch könnte alte erneuern, dass wäre dann nicht so teuer.. ErfaSure, here is the translation of the text from German to English: "Suggestions/tips?"

Bosch also offers replacement injectors (and BMW certainly does too). There are definitely replacement injectors available for VW TDI engines (with the VP37). You can get them for a much lower price. I mean, my FOUR injectors cost around 350 euros total for replacements from VW. If you want a complete set of new injectors, they cost around 1000 euros even from VW.

Best regards,
Jan.