525d runs on 4 cylinders during startup and smokes excessively.

Hello.

I'm having another problem, unfortunately.
I replaced injectors number 3 and 4; they were defective (a return flow test was performed by a trusted mechanic).
By the way, I also cleaned the EGR valve.
Okay, here's the translation:

"Now I'm having the following problem:"
When the engine is cold and I start it, it only runs on 3-4 cylinders, and a HUGE cloud of blue smoke comes out the back. If I give it a little gas, it then runs on all cylinders and normally. The engine actually starts very well, and when the engine is warm, this symptom doesn't occur anymore.
However, when I'm driving below 2000 RPM and going slightly uphill, I notice the car stutters, shakes, or jerks again. But the power is normal. It's like a kind of "misfire." However, when I'm above 2000 RPM, I don't feel any more of that stuttering. This symptom occurs both in cold and warm conditions.
Due to the weekend, I haven't been able to read the error codes yet.
Did I damage the AGR (Abgasrückführungssystem) or do something wrong during the injector replacement?
I also read something about a fuel injector calibration process performed by a mechanic using a computer, especially when replacing more than one injector.

HELP! Thank you for your help.

Andi.

It's a 525d model from 09/02 and currently has 283,000 km on the odometer.

Is this the CR-1 or the 2nd generation?
Does the vehicle have a fuel cooler?

Hello!
There are several numbers printed on the injectors of your machine. You need to write these down from the new parts and then have them 'registered' at BMW in the MSG (presumably a service center), and then, if there are no more defects, your engine should start running again.
'When you replaced the injector, did you also check the intake manifold to see if all the flaps are still there? They tend to come loose easily, and the symptoms afterwards often indicate an injector problem, which is also frequently misdiagnosed by BMW workshops.' When they do the exchange, they usually realize that replacing the injectors is not the only repair needed...
Regards,
Dominique.

Exactly, the first generation still had aluminum flaps. If the motor has been sucked in, it will be a somewhat more exciting repair.

In this case, the car will also not warm up properly.

I would start by registering the new injectors, then check the oil consumption, and finally check the compression.

Good luck.

efistho