[Daveyvtec]

Hi all, so as the title suggests, I have an issue with surging at 1500rpm with very little throttle applied. The car begins to jerk/lurch, it’s pretty noticeable. Once I apply throttle, it’s gone. And it only happens around 1500rpm. There is a little shakiness at idle when the revs raise as the clutch is released a little.

It’s a 2015 318d, timing chain has been done about 8000kms ago, car is regularly serviced at 10k. It is remapped and EGR deleted. The EGR is still in situ but is closed.

Has anyone else experienced this issue? Can anyone shed a bit of light as to what may or may not be causing it? I’m just looking to be pointed in the right direction. Maybe what sensors to look at or are there any sensor values I can check in BimmerLink.

After I got the EGR mapped closed I took it out and cleaned it. I’m thinking to do the same with the inlet manifold and swirl flaps. I’m hoping it’s just a carbon build up. The DPF is clear.

Any help would be much appreciated. Thanks

[Eddamoo]

Every thread I've seen about this kind of hesitation has always been EGR related, including a few threads where people said their EGR was mapped out. I suspect either people aren't mapping them out properly or something is stuck open - they're probably just removing the error checking instead.

A way to diagnose a leaking EGR is checking your MAF Actual vs Requested logs. If you see the actual reading bouncing around with a steady requested, that means unmetered air is likely coming from your EGR.

I would always add a blanking plate to be certain.

[n00bkiller944]

Hmmm. I am getting a lurch as well at low RPMs in low gears. Wonder if I am seeing the same unmetered air coming through my EGR. I will do some data logs, smart call.