2010 2.4 TDCI Problems

[SteveB67]

Hi Guys, hope you can help
It is fine driving around local country roads up and down hills, but hit a dual carrigeway/motorway and do 70-ish miles per hour for 10 miles or so and it goes into limp mode. NO lights on the dash, no overheating according to temp gauge. Turn off the engine and re-start and it resets itself, back to normal.
MAF sensor and MAP sensors both replaced with genuine parts. EGR valve replaced in the last 18 months. intercooler pipe replaced as split.
Shows fault codes
P0234 Turbo/supercharger overboost condition
P1103 Mass Air Flow Sensor in range but higher than expected
Any ideas more than welcome.
Cheers
Steve

[grogan197]

Has it got a tuning box plugged in? I've heard these can cause overboost.

[knobby1]

Hi Guys, hope you can help
It is fine driving around local country roads up and down hills, but hit a dual carrigeway/motorway and do 70-ish miles per hour for 10 miles or so and it goes into limp mode. NO lights on the dash, no overheating according to temp gauge. Turn off the engine and re-start and it resets itself, back to normal.
MAF sensor and MAP sensors both replaced with genuine parts. EGR valve replaced in the last 18 months. intercooler pipe replaced as split.
Shows fault codes
P0234 Turbo/supercharger overboost condition
P1103 Mass Air Flow Sensor in range but higher than expected
Any ideas more than welcome.
Cheers
Steve

MAF & MAP sensors rarely fail...it's usually a duff/sticking EGR which causes these codes.

Lord Knobrot

[SteveB67]

Cheers Knobby,
That was to be the next avenue to explore, that, or the turbo actuator. Cheapest option first It'll be getting changed on Wednesday.
Cheers
Steve

[knobby1]

Cheers Knobby,
That was to be the next avenue to explore, that, or the turbo actuator. Cheapest option first It'll be getting changed on Wednesday.
Cheers
Steve

Does it have an electronic turbo actuator..?? A 140PS RWD for example?? If so the actuator would throw up a different fault code if it were indeed faulty.

Lord Knobrot

[SteveB67]

Yes, it's the 140PS one with the electronic actuator. Those two fault codes are the only ones that have appeared.
Thanks again
Steve

[knobby1]

Yes, it's the 140PS one with the electronic actuator. Those two fault codes are the only ones that have appeared.
Thanks again Steve

Fair enough....you might be able to just pull the EGR and give it a good clean, they can stick sometimes.

Lord Knobrot

[SteveB67]

Well i finally got round to replacing the EGR valve. The old one was goosed, once off it rattled like an old tambourine!! Even though it made the sounds of going through the cleaning routine.
But, it has still made no difference to the original issue.
So, so far
MAP sensor replaced
MAF sensor replaced
Intercooler hose replaced
and now EGR valve replaced

Engine is absolutely fine driving around on normal roads, for miles and miles with no issues.
But throw in dual carriageways and motorways cruising at 70 and above and then come to an incline and as soon as you touch the accelerator, it loses power and goes into limp mode. If i then pull over turn off the engine and then restart it goes back to normal.
It is still showing the original fault codes

P0234 Turbo/supercharger overboost condition
P1103 Mass Air Flow Sensor in range but higher than expected

Any more ideas?

[knobby1]

P0234 Turbo/supercharger overboost condition
P1103 Mass Air Flow Sensor in range but higher than expected Any more ideas?

These two codes still point to a duff EGR...another possibility, have you had the intercooler off and cleaned all the oil residue out of it?? Also the inlet manifold off and cleaned all the crud out of it ...and the inlet ports in the head..?? They fill with oily spooge and the ports can indeed become quite clogged....mine had the same codes come up under the same circumstances, it had only done ~50,000km when I looked at the manifold/ports whilst I was replacing glow plugs one day... and it was horrible in there.... If the manifold/head can't breath properly (and since there's no throttle valve like a petrol engine), the boost pressure & air flow at full noise might build up more than the manifold/ports can handle..! I guess a clogged muffler or cat could indeed do the same thing..Just thinking out loud.. I've not had the same codes come up since I replaced the EGR and cleaned out the manifold and head inlet ports, my machine has been remapped and now produces a bit more boost than normal too.

Probably all a load of twaddle from me as usual.

Lord Knobrot

[SteveB67]

Replaced EGR with brand new genuine part. Haven't looked at the intercooler or other stuff yet.

Any pointers/clues are always welcome

[Jim Archer]

Had a good quality fuel filter recently?

High speeds point to fue supplyl or the turbo sticking.

Jim

[Ml Autos]

You have overboost condition!! Turbo actuator or variable geometry are your first steps

[knobby1]

You have overboost condition!! Turbo actuator or variable geometry are your first steps

I suspect if the actuator or the VNT part of the turbo was playing up, it would throw up a code.??

I accidentally forgot to reconnect mine whilst I was fumbling around with the loom, it threw up a code as soon as I turned the ignition on.

Lord Knobrot

[Ml Autos]

P0234 Turbo/supercharger overboost condition Not good enough?

[knobby1]

P0234 Turbo/supercharger overboost condition Not good enough?

I used to get that code... and P0299 (underboost) along with it...changed EGR and has been fine since...nearly 2 years since I replaced the EGR. My turbo still works fine. There's a "Turbo function test" within IDS to see if the turbo, actuator and/or VNT are working properly.

Lord Knobrot