2015 scenic 1.5dci 110 P0299 fault

[Neal R19]

Hi all,

Got a bit of an issue with my wife’s scenic – 2015 1.5dci 110

She notified me (a couple of days after it first appeared ) of the display showing the dreaded ‘check anti-pollution system’ and ‘check injection system’ messages. Fearing the worst (some kind of DPF issue) I scanned it and found only a pending P0299 which is a turbo underboost fault. I drove the car and found that indeed it was very sluggish, with the turbo either not boosting or only minimally.

Datalog:





I did some mechanical diagnosis and found the boost solenoid to be stuck shut. I blasted it through with brake cleaner, freed it up, refitted and the car once again boosted correctly and drove as normal. Then after a short time the solenoid got stuck again so I bought a new one and fitted that. All good, confirmed by datalogging – boost pressure follows demand fairly closely, certainly not underboosting. Arguably it's overboosting on overrun but I'm not sure what good or bad looks like?





Only issue is that the pending P0299 code (and the messages on the dash) won’t clear. Can anyone confirm what conditions need to be met for it to do so?

 

[Adey]

sometimes the more modern stuff needs a certain amount of miles or cycles to clear it.

Clip, Renolink or similar may be able to clear it though

 

[Brigsy]

There will still be faults stored if you scan it with clip. The generic obd readers lead you up the garden path with the diesels.

 

[Mattjoss5]

Have you checked the exhaust pressure sensor and the pipe from it to the dpf isnt blocked ? should show on live data

 

[Neal R19]

Have you checked the exhaust pressure sensor and the pipe from it to the dpf isnt blocked ? should show on live data

Yeah, forgot to mention, I did check the pipe to the sensor at the RHS of the engine, if I take the sensor out and start the engine, there is exhaust pressure there.

I added PR009 and PR041 to Torque get the boost pressure and demand readings but I don't know which PR would correlate with the exhaust pressure sensor to monitor it. It's not a standard one on Torque.

 

[Neal R19]

Bought a hooky renolink...

 

[Adey]

Bought a hooky renolink...

great bit of kit, can be dangerous though. Take pics as you go so if you change something accidentally, you can type in the old values

 

[Neal R19]

Right, got the Renolink up and running.

Connected to the car, scanned for ECUs, had a poke around looking at stuff, didn't 'write' anything.

Can't see how to even do something as basic as look as DTCs

Not only that, but I now additionally have 'check ESC' and 'check hill start assist' on the dash too.

FFS

 

[Adey]

checking dtc's is done per ecu. Top right of the screen

 

[Neal R19]

Right, went for another go after dinner.

The ESC and hill start faults have disappeared on their own.

Figured out how to get at DTCs.


Cleared 'em all down and the messages and MIL have gone away.

Let's see if they stay gone.

For now though, all good

 

[Turbell]

Inferno 225 Meg throws a few extras in when it's had issues in past, last time when rear ABS sensor went, threw a couple of bonuses in, injection related if I remember right, if I hadn't got Clip and without the help I've got off here , it'd been kicked into touch long ago.