2016 V40 2.0D Stutter at 1500rpms when feathering throttle

[SwedezChips]

Hi everybody,

My car is a 2016 Volvo V40 2.0 Diesel. Absolutely lovely car but it’s developed a stutter/hesitation when going even slight uphills at roughly 1500rpms when feathering the throttle/ cruising along. Sometimes it feels as though I’ve lifted off the throttle and other times it can be a more violent jerk.

The car threw the code P04D9 - Closed Loop EGR Control At Limit - Flow too low.
Local garage naturally thought EGR valve and cooler must be blocked so had them cleaned. This did not cure the problem so we blanked the EGR but we still have the problem.

So far what I’ve had done:

EGR - Deleted
Exhaust pressure sensor (back of engine) - Cleaned
Map sensor - Replaced
Air filter - Cleaned
Fresh tank of supreme diesel fuel
Fuel filter - Replaced
Throttle/brake sensor - integrity tested all okay
Swirl flaps - disconnected

Still having the problem and it’s not throwing any other codes. A smoke test on the vacuum pipes revealed smoke coming from this plastic structure at the back of the engine. Could this be the cause? What is it? I’ve attached a photo of it.

Any help would be greatly appreciated guys I’m literally at the end of my tether with this car.

[SwedezChips]

So that part is a breather/filter and smoke coming from that is fine which means I have no leaks.

What would be the next test to conduct? Thanks

[Linx]

Originally Posted by SwedezChips

So that part is a breather/filter and smoke coming from that is fine which means I have no leaks.

What would be the next test to conduct? Thanks

HI,

Did you get to the bottom of this? I have a similar issue on my D4.

Cheers.

[SwedezChips]

Originally Posted by Linx

HI,

Did you get to the bottom of this? I have a similar issue on my D4.

Cheers.

Hi, yes I did

It was the EGR Cooler blocked after all that.

Originally he only cleaned the EGR valve. Mechanic gave it a good solid clean out. Was choked to death with carbon soot.

Hope this helps.