Metering pump troubleshooting: A different approach?

hello,

ich fahre 2 volvo tdi mit dem 5zyl. AEL motor.

One has a manual transmission, and the other had some strange jerking at idle or when rolling. In that case, the fuel metering unit was cleaned and adjusted, and that fixed the problem.

Now, I'm experiencing a very similar jerking sensation in my second car, and it feels exactly the same. However, it only happens when the automatic transmission is in "D" and I release the accelerator, essentially using engine braking.
When I shift to "N" and then engage drive, the jerking stops.

Actually, I would probably suspect the transmission/drive system, but since the jerking is exactly the same as the jerking caused by the metering unit, I thought maybe someone here might have an explanation for it?

Unfortunately, I haven't been able to find a mechanic who can diagnose the problem. Some want to replace the entire transmission at a high cost, while others suggest simply changing the transmission fluid.

I'm currently investigating the cause, and I'm grateful for any tips.

best regards, uwe

Sorry, one more question. I just found a great tutorial.

Unfortunately, the OBD function doesn't work on this Volvo, but the manual states that it should also work without it.

Should I really try cleaning the MSW (module for steering wheel functions) myself without using an OBD (on-board diagnostics) tool?

"Thank you."
best regards, uwe

It depends on how comfortable you are with using screwdrivers. I wouldn't dare to try it myself, I've been through all of that before and was just happy to have the OBD (On-Board Diagnostics) system.

Best, Bill.