I repeat regularly – expensive and responsible spare parts purchase only from a reliable supplier. This time – about my success in the purchase of the spare parts. I hope my experience will be useful. Conclusions – at the end of this entry.

This time the story about my everyday car, whos N53B30 engine has a mileage of 500’000km. I will mention only facts, maximum compact.

In three cylinders: injectors of 07 and 09 releases, whos resource is at least 350’000km without slightest problems.

In the cylinder No.4 – injector of 11-th release installed more than a year ago, purchased from one of the wholesalers, and performs perfectly for at least 100’000km already. Reason for the replacement – previous injector (07 release) started to leak in idle. Unfortunately, it happens – for example, due to micropart, stuck in the nozzle of the injector, this is a typical defect.

In the remaining two cylinders, during the last 100’000 (around one/one-and-a-half years), four injectors of 11-th release in each cylinder are replaced!

All replaced injectors are supplied by the same supplier (different from previously mentioned) – this is the unifying component.

Defects of the injectors:

  • after a 9’000km in Stratified charge by the average required torque (70 .. 100Nm), strong detonation/misfires started in the cylinder. Defect stable. At the same time – all parameters of the injector and bank, adaptations – correct;
  • after 40’000km, the nozzle started to stuck in an open condition. Interval: 200 .. 500km. For 5 .. 10 seconds, the injector stuck in the open position. 7 events waited before replacing the injector;
  • directly after installation, increased misfire density in Stratified charge observed; adaptations and Lambda – correct; after 15’000 – 20’000km the injector replaced;
  • directly after installation, strong “floating” of the chemical efficiency observed during Stratified charge (till +1.50mg/stk). For approximately 5’000 .. 10’000km, the defect is progressing – floating becomes swift, short-term vibration of the exact cylinder appears. After a while, irregular shivering of the engine starts (misfiring not as a cause but misfires as a consequence due to the inadequate amount of injected fuel). Finally – 4 events observed, during which the injector stuck in the open position for 5 .. 10 seconds. This problem is not solved even by switching off the engine several times and switching the HPFP in the emergency mode; total resource of the injector around 30’000km;
  • directly after installation, significant flowrate difference from the planned is detected, defect progresses during time. Finally, DME detects that the injector “falls out” of the allowed corridor;
  • quite regular “leaking” in idle – shortly after installing, the injector started to leak strongly in idle for several times. Offset adaptations on Stratified charge mode fell out the allowed corridor.

In all cases, previously identified defects completely disappeared after replacing the current injector. After the first two cases, I thought: coincidence. After 6+ cases… I see two possible scenarios:

  • in my case, the percentage of the defective (new) injectors makes up 100%, defects – quite untypical; the manufacture of the injectors suddenly is not able to manufacture a quality product or deliberately sells brack;
  • injectors, purchased by me, actually are for example used, but – cleaned (probably, sorted out without severe defects or wiped with some chemicals) and packed in the boxes of new injectors.

All injectors were purchased from a cooperation partner, who said, that they are obtained from the dealer in Germany. Now the version is slightly different – injectors were acquired via an international wholesaler, who purchase them from the dealer in Germany. Unfortunately, the injectors were obtained without any documentation and warranty. Accordingly, – I have bought a pile of defective injectors. Of course, these are lies, because the purchase of the spare parts for a legal person (company) from an authorized person (company) is not possible without any accompanying documents. No doubt – my ex cooperation partner lies to me – avoids any responsibility in this situation.

The situation is quite dumb. I did not even want to save any money. I had that cool “team” feeling when the cooperation partner organized the deals. I don’t have suspicions, that the cooperation partner had deliberately sold any defective spare parts. His profit from the sale – most probably, negligible. Yes, if I would know that a massive seller of the spare parts sells its products as if without documentation and warranty – I would consider such an offer as very suspicious. I would not choose such a supplier. But – I did not know it, because I trusted the cooperation partner.

Sentence of this entry: unfortunately, we can not know who is a “reliable” seller, who – a fraud. So I modify my suggestion: responsible spare parts purchase only from the dealer! Keep the purchase documentation! If the service installs the spare parts, ask for documentation! Including:

  • in which cylinder;
  • by which mileage;
  • which encoding data (of the injector);

or any other specific signs of the installed part. Only if you have the purchase and installation documentation, you can ask for the fulfillment of warranty obligations.

Yes, I’ve lost around EUR 1500, not even counting the time. Yes, I have no slightest illusions that anyone of the supply chain will react in any way. You can learn from my experience. Don’t do it like me!