Today’s example: N53 series engine. The car has NOXEM installed, and the engine uses a Stratified charge. The car has new injectors (manufactured in the Year 2022) installed (purchased via BWM dealership – the owner of the vehicle gave all proofs that the original product has been purchased).
Unfortunately, the car is shivering at idle, and there are problems with a cold engine – a very distinct fuel smell and exhaust smoke.
As usual, we start with the error message list. As the error messages have been deleted, let’s check the History list for the recent recordings.

Here, the error messages 2FCA and 2FDA typically indicate strong leaking of the injectors during cold start; 2C7E suggests severe problems with the injectors/fuel mixture.

In the continuation of the list, we see that cylinder No.1 has been switched off due to misfires. And additionally – problems with the fuel mixture of the 1st bank.

At the end of the list – switched-off cylinder No.3 and ongoing problems trimming the Lambda probes.

The owner of the car sent me injector data for idle, Stratified charge mode:

The 1st cylinder injector has poor atomization; injector No.4 leaks in the closed position.
On the next day, injector data looked like this:

Problems with the 1st injector became even more severe, and now the injector of the 5th cylinder leaks too.
In addition to all this – substantial differences in LTFT between both banks:

What could happen to new, original injectors?

At this moment, I asked the car’s owner – maybe he was using some fuel additives.
Yes, but of course! There is a wonderful additive:

Archoil AR6900-P Max Advanced Petrol Synthesis

I did not have any additional questions. But the owner of the car how has several questions – what to do with damaged injectors, where to find finances to purchase new injectors, and on which service to rely for complete cleaning of the fuel system.