V60 CC 2.4 D4 autobox problem

[Kev0607]

Originally Posted by gianmarko

roger that
i read elsewhere that a specific fluid is needed. i think i saw a reference but cant find it.

It will take JWS3324 fluid, also known as AW-1.

You must use this transmission fluid in your car. Older cars used different spec fluid, but that won't work for yours.

With regards to a partial flush as opposed to a full change... Its basically a less "aggressive" way of changing the fluid when you drain and fill it. If you change it all at once, there's a chance that dirt could be dislodged and get trapped inside places it shouldn't, causing shifting issues. Also, access to do a full flush is tight. The clips are usually brittle and break. Its easier to do drain and fills.

Your car only has 84,000 miles. The fluid, in theory, shouldn't be that bad colour wise. I wouldn't expect it to be completely black with that mileage. 3 drain and fills will renew well over 90% of the fluid.

[gianmarko]

I ran the 159 for a loing time with the EGR physically blocked and no issues with regen.

for what i can see, the regen will run the engine in a way to raise the DPF at high temperature and burn the particulate (making much smaller particulate )

dont think EGR would affect that much if at all.

I will just go for a remap of the EGR and no blnking plate for a start and see what happens.

it might not be the EGR after all

i ran the car in S mode (where i assume the autobox wont shift gear on its own) and noticed the same stuttering so EGR looks a prime suspect to my untrained eye

Originally Posted by Simmy

if you get rid of the egr your car may experience difficulty regenin the dpf as the egr is part of the regen process check the duty cycle of the egr to see if its working within parameters bad connections at the injectors have been known to give gearbox faults with your diagnostics check the tcm for any faults like intermittent signal

[gianmarko]

Stuttering got much worse, and looks more like an engine issue....

[Stu B]

Originally Posted by Kev0607

To save posting another thread, but its a similar subject...

Hi Stu,

I'm planning on doing a gearbox service when I clean my EGR valve out... Makes sense to do it then I think, especially as the airbox has to come out of the way to clean the EGR/throttle body. I'm also going to change the oil earlier than its due because of the issues I've had with the swirl flaps.

My oil service technically isn't due until January next year, but like I said, I'm doing it early and will change it again in January 2025 just to keep the maintenance up. I don't want to change my service date... I remember January, as that's when the MOT is due

Do you think a single drain and fill of the transmission, then repeat it in January would be okay? Or is that too long?

Hi Kev, yes definitely - I agree with Simmy, any regular gearbox preventative maintenance is worthwhile in my view.

Stu

[Stu B]

Originally Posted by gianmarko

Stuttering got much worse, and looks more like an engine issue....

Sorry to hear that, keep us posted with your findings!

[Kev0607]

Originally Posted by gianmarko

Stuttering got much worse, and looks more like an engine issue....

Like Stu, I'm sorry to hear this.

With it being a diesel engine, I suspect the following;

-Fuel filter needs replacing
-Dirty EGR valve/throttle body
-Turbo vanes sticking
-Injectors or injector wiring

[gianmarko]

Thanks. i thought about fuel filter but car has been allegedly just serviced so should be new.
checked the DTC and no errors. also did some logging while driving but could not see anything special

i was surprised to see fuel rail pressure varying from 20000 to 150000 Kpa depending on throttle settings and rpm.

Originally Posted by Kev0607

Like Stu, I'm sorry to hear this.

With it being a diesel engine, I suspect the following;

-Fuel filter needs replacing
-Dirty EGR valve/throttle body
-Turbo vanes sticking
-Injectors or injector wiring

[Kev0607]

Originally Posted by gianmarko

Thanks. i thought about fuel filter but car has been allegedly just serviced so should be new.
checked the DTC and no errors. also did some logging while driving but could not see anything special

i was surprised to see fuel rail pressure varying from 20000 to 150000 Kpa depending on throttle settings and rpm.

Not necessarily. It depends what service the car had. Some services include a fuel filter (full service), some don't (interim). You may get a surprise when you change it...

Start with the basics. A fuel filter is cheap.

[GrahamBrown1]

Originally Posted by gianmarko

i was surprised to see fuel rail pressure varying from 20000 to 150000 Kpa depending on throttle settings and rpm.

This is normal, depending on engine load, 20,000kpa is approx 200 bar. This is the very minimum required for the engine to run with no load. 150,000 kpa is approx 1500bar which is when the engine will have been under high load. These are a 1600bar system so max power is produced at higher fuel pressure.

[Simmy]

Originally Posted by gianmarko

Stuttering got much worse, and looks more like an engine issue....

try a leak backtest on the injectors after the filter change inspect all injector connections for loose wires and or corrosion/or breaks. in an ideal world profesional diagnostic equipment would make fault finding much easier.