It is essential to find the right specialist. Exactly the specialist (typically – the mechanic) will define which spare part will be replaced, which – is considered “good to go”.
The N53 owner, which was already in deep despair, approached me. He spent a lot of money on the car’s repairs, but there was no result. The mechanic tells him to replace one spare part after another, but – the engine vibrates, and not all cylinders are working and are shivering.
Parts which already have been replaced:
a. spark plugs (NGK installed);
b. ignition coils;
c. injectors (all of them purchased at the beginning of the Year 2022 from a BMW dealer);
d. CO catalytic converters;
e. last one, when the mechanic run of ideas – the NOXEM was installed.
I have no objections regarding the replacement of spark plugs and ignition coils. The spark plugs should be changed quite often for these engines, and the ignition coils are not eternal too (in addition, Bosch coils cost only around EUR 25 .. 30/piece).
The situation with the injectors is more interesting. All of them (one after another) were detected as “damaged” by the mechanic. What happened to the old, “damaged” injectors? They have been given to another specialist for “repairs,” and this specialist has given the verdict that all of them are electrically damaged and are not repairable. What, please? Electrically damaged? In my experiences (from several tens of thousands of injectors), only several have been damaged electrically. But here – 6 from 6. How is that possible?
The answer – of course, is that injectors have no electrical defects. This time the “specialist” don’t knows how to use the test equipment (there are such examples in my blog) or – has deliberately lied to get himself good injectors (all injectors were of release 11, made in 2017, with a small mileage). Considering that the injectors were of the last release, relatively new, I assume the second option is the most plausible.
So – unjustifiably spent EUR 3000 for new injectors, and (most probably) the old/good injectors are lost.
Why do I say – unjustifiably? To evaluate the performance of the injectors:
a. the NOx system should be repaired; then DME will restore the Stratified charge and measurements of the injectors;
b. conclusions should be made based on the injector measurements.
In this case, the NOXEM was installed not as the first in the chain of “works to do” but – as the last one. Accordingly – when the old injectors were identified as “damaged” and after installing the new ones – DME was not using Stratified charge, and the injectors were not measured. What can you hope for in such a situation?
But – what could go wrong after installing the new injectors?
In the error message list – error messages regarding turned-off cylinders No.1, 2, and 3; error messages regarding CO catalytic converters.
INPA shows the following data:
These are the chemical efficiency tests of new injectors in Homogenous mode. As we see, there are serious problems in the 1st bank! It is even hard to identify the culprit! It is no wonder that regularly all three cylinders (in random order) are switched off.
But how is that possible?
Unfortunately, all these injectors, purchased at the beginning of the Year 2022, are actually industrially refurbished by the manufacturer (VDO). Quality of these restored injectors – game of luck. Not without reason, BMW recalled these injectors during the recall campaign (it happened in the spring/summer of the Year 2022). Unfortunately, there is almost zero possibility that the vehicle owner will be able to exchange them because already by the purchase, the dealer has warned that the warranty is “till the door”. The arguments of the dealer, why:
a. it is not possible to indicate if the current injector is actually purchased at the exact time/place (if the replacement is not performed by the dealer);
b. there can be damages due to incorrect installation.
Regarding point “a”, I have an objection – the injector contains both data of manufacture and encoding. These are unique data and allow us to check the conformity to the purchased one. Regarding “b” – it is hard for me to think of any hidden (invisible) defects which can be caused due to incorrect installation. And what could be an incorrect installation at all? But there would be no quarrels here if the injectors were replaced by the dealer.
Anyway – this is another example in which new (actually – refurbished) injectors fail.
The owner of the car (most probably, following the suggestion of the mechanic) entrusted the replacement to the mechanic, not the dealer. As if a small amount of money was spared, but – the warranty on the injectors was lost. The mechanic earned his money, but the owner of the car – “bought” himself problems and huge additional expenses.
One more interesting nuance:
The marked item – Delay parameter compensation parameter of the injector of the 3rd cylinder (it corresponds to the injector’s data – the car’s owner sent me the picture of the injector).
Previously (when the injectors were new, not refurbished), such – significantly different from the average value – parameters have not been seen. Yes, formally, this number “fits” in the allowed corridor, but – it indicates a significant parameter difference from the planned ones. Obviously, something was not “perfect”…
And finally – what could happen to the CO catalytic converters? In the DME error message memory, the error messages regarding CO catalytic converters are recorded. This is the reason why DME still is not using Stratified charge.
It turns out that the CO catalytic converters of the car have been replaced (according to the mechanic’s suggestion). Not OEM, but “alternative” products have been installed. Here I would like to repeat – for N43/N53 series engines, only OEM CO catalytic converters can be used! No alternatives!
At this moment, the set of CO catalytic converters for N53 series engines costs around EUR 4000 if, within the exchange program, the old (of course, OEM) catalytic converters are given back. If there are no old catalytic converters (as in this case), the bill will be around EUR 7000!
This is an educational story, when, following the mechanic’s recommendations, a lot of money has been lost and… Huge expenses are only to be expected.
Sentence of this entry – do not replace parts without justification! Ask to perform the engine diagnostics and ask for justification of any action. Ask to show the diagnostics data, which confirms the damage to the spare part. If the diagnostics specialist is not able to justify his conclusions or if the guessing starts – change the diagnostics specialist! Repeated diagnostics will be much cheaper than the unjustified replacement of expensive spare parts.
