Unstable return to idle when revving

[lizzard-t]

Depends on what load the car is under is your friend car the same make and model ?
but has anyone actually looked at the egr or suspected it ?
wuth diesels you do need to clean the egr and pipe work regularly.
if that ant been done then that garage requires a check up from the neck up

[Aurega]

Yea, same model, engine, year, everything

I did, and clean it... not much of carbon build up... Not sure which other pipe to clean...
How Can I identify that the EGR is bad?

Picture in attachment.

thank you !

[lizzard-t]

Use a vacuum gauge to check the vacuum supply hose for vacuum at 2000 to 2500 rpm no vacuum at normal operating conditions would suggest a loose hose s blocked or faulty ported Vacuum switch or a faulty vacuum amplifier or pump
If you have a bi-directional scan tool activate the EGR when engine running and check the vacuum end of the pipe if the solinoid dose not open when energised is either stuck or In the open position or closed
But with a faulty egr you would have a code stored ..
But that valve looks dirty

[Aurega]

Hello, so I tried to read the trim but it does not work not sure why its grey on diagnostic...

[Aurega]

Is it posible on B20DTH to remove EGR return pipe without removing the engine from the car?

[Aurega]

Hello,

we did not find anything Is it possible that it can be cause by DPF ? I still do not have any error but it looks to me that car cannot breath or something...

thank you

Jan

[lizzard-t]

You need to check your fuel trims as stated before.
are you just guessing ?
you can look at the saturation levels of your DPF on most diagnostic tools .
if you have excessive back pressure then it will be causing poor starting , car not able to spool up the turbo .poor drivability.
in worse cases it will start to blow oil seals and can render the car useless.

[Aurega]

I was not able to load the trims even on the Bosch diagnostic... This is diagram of fuel presure and on those spikes the engine swings... any idea please?

[lizzard-t]

Cannot read the information.

[Aurega]

sorry here is full resolution - https://photos.app.goo.gl/Vzu3KVXEF1B5Xkfn6

[Aurega]

Hello did you check the diagram please?

[lizzard-t]

Hello.i still cannot see the graph properly.
If you have the original.then take a picture of it then upload it that way.

[Aurega]

Hello, original https://photos.app.goo.gl/6BmsVUdfFJ7DWUH18

Thank you!

[flusher]

the garage that replaced injectors and fuel valve did check that pressure stopped from going down on pedal release?

[Aurega]

Not sure what you mean by "stopped from going down on pedal release"?