Fault codes 07144 & 05171

[Juff757]

Hello All,
Wondering if anyone is able to shed any light on some Carista codes, as I'm out of ideas.
Van went into limp mode with flashing glow plug symbol and generated codes
07144 - Data bus on board diagnostic interface: check DTC memory
05171 - Turbo/supercharger under boost
local garage who was fully booked for over a month suggested EGR as a likely culprit, so I changed it {valve was seized closed) but fault remained. As the van had a loss of power and sight judder when accelerating before going into limp mode I feared a turbo issue. Had the time, so replaced the turbo (won't be doing that again, right pain} with a refurbished one, but problem persists. Any ideas? TIA
2016 T32 140ps 2.0 TDI CAAC 75K miles

 

[mmi]

Have you checked the intercooler?

P0299, coil light flashing and a whooshing noise from under the car

Driving back from fishing today and VAN start whooshing very loud when accelerating hard, then lost power and start smoking black, then the coil sign start flashing and went to limp mode. I scanned the code when got home and got P0299. I checked all the EGR pipes and the intercooler hoses and...

www.t6forum.com

 

[Juff757]

No I haven't. Not a bad idea thanks. That's a job for tomorrow.

 

[Juff757]

Thanks MMI, yup it was the intercooler. All sorted now. Cheers

 

[Steve1978]

I’ve just had this same code on mine. Exactly the same symptoms. I’m not in limp home mode but everything else is the same.

What exactly was wrong with the intercooler? Did you just replace it?

 

[The Bear78]

Boost leak.
Either a pipe has split or come off or there's a hole in the intercooler (probably!!). The clamping system between the soft and hard pipes is quite secure. However, the fitting at the intercooler just pushes in and is locked by a wire clip. I've found this connection problematic in the past, albeit with aftermarket parts.
I replaced my intercooler a couple of years ago after similar symptoms. The intercooler itself has thin reinforcing bars welded across the core. Mine had broken away due to rust and the boost pressure was inflating the core like an accordion! This constant flexing eventually cracked and air was hissing out if the core. I could actually feel it at idle and there was a tell tale oil mist on the bumper.

 

[Steve1978]

Thank you I will take a look when I am home, is it a bumper off job?

Just had a look underneath and their appears to be oil. Funily enough the oil light came on last week and I just thought it had burnt some off.

So symptoms:
Oil light comes on, I’ve topped it up about half a litre

4 days later coil light flashing and turbo error in carista. Same symptoms as you but there is some oil splatter on the subframe.

 

[Juff757]

Definitely would take a look at the intercooler. It is a bumper off job. Mine didn't look too bad it was a slight oil leak that gave it away, didn't pressure test or anything. I did have a reduced power (seemed like it anyway) before it went into limp mode, but no noise of air escaping etc.

 

[The Bear78]

@Steve1978 it's possible that oil is leaking from a pipe in the induction system but this should be a small amount. It's only oil mist from the engine breather system so would take a while to build up enough to drip. It certainly wouldn't contribute to any measurable oil consumption.
Perhaps you have a combination of things going on. Either way, find the source of the oil leak.
Out of interest, did you only need half a litre when the light came on?

 

[Steve1978]

Yeah just half a liter and light went out.

I think you’re right this has been going on for a while. I did a service yesterday. Dropped oil changed oil and air filter. Left it running for a while and no drips as yet.

When it’s stationary it revs fine and sounds fine. When it moves I can hear like a psshhh or a suck. Just like a high pitched noise, like an air hose. But only when moving.

Then I get the coil light and loss of power. Stuttering along

 

[Steve1978]

So I know this post has become a bit of a Frankenpost but i thought I would update here anyway. took my intercooler off and its had a 3 inch crack in the bottom cooling pipe. Got a new one from GFS and fitted that, whole job took about 3 hours.

Took it out and gave it a bit of a blast and all good, when i got back though the hoses seemed loose. the had popped out on one side, both hoses. This makes me think that the £130 for the GFS might be cheap for a reason!

I am dragging a caravan for a hundred miles at the weekend if it survives that then its passed the test, if not then i will return it and get a better one. are there "better" ones?

 

[The Bear78]

Maybe you have a different cooler to me. I don't recall any cooling hoses, just the main air pipe. My GSF replacement wasn't the best but has been fine in the year or so since it was fitted.
Obviously OEM will be better/best but they are around £300+

 

[Steve1978]

Maybe you have a different cooler to me. I don't recall any cooling hoses, just the main air pipe. My GSF replacement wasn't the best but has been fine in the year or so since it was fitted.
Obviously OEM will be better/best but they are around £300+

Sorry it’s the big hose on the right. The one that’s a bigger to fit!

I just went out and covered about 20 miles and the intercooler is still fine but I managed to get a puncture.

That’s an and fault, intercooler popped and a tyre in one week! What a week!