P0299 Fault

[schtall]

Hi All,

I recently purchased a 2014 Transit Custom 2.2 with a failed turbo, since replacing the turbo (alongside other items) I keep getting a P0299 Underboost fault and I’m now a bit stuck as to what is causing it. Notes so far -

• Turbo is new/reconditioned from London Turbos, spins freely, no excessive play on shaft, VNT mechanism free
• Oil, oil filter, air filter & turbo oil feed pipe replaced. Drain pipe checked, cleaned and refitted
• DPF brick has been removed by previous owner
• Cam cover replaced as breather was blocked
• Injector seals replaced during cam cover swap
• Glowplugs replaced
• Inlet manifold & throttle cleaned out
• EGR valve replaced
• Hoses & intercooler inspected for leaks – nothing obvious
• Forscan data shows demanded pressure (DMP) match actual pressure (MAP), which to me contradicts the fault somewhat. Boost pressure actuator drops out when the fault appears



Any ideas what to check next?

Cheers,

Chris

[sherwoodcycles]

Have you checked the boost pipe from the radiator. It can rub on (I thjnk from memory) the alternator mounting bolt which will eventually break a hole (you can normally hear a hiss when driving )

[schtall]

Yes, all pipes & intercooler checked with smoke tester, no leaks...

[sherwoodcycles]

This might sound daft...is the actuator the correct one in the correct position ? The rwd has an almost identical turbo but the actuator rod is 180 out of phase (if that makes sense)

[sherwoodcycles]

Also as (from a quick read) it can be caused by blocked dpf...(you said yours has been removed)...After the dpf there is a openy closey valve thing in the exhaust pipe. Have you checked that that is able to do its thing ? (Sorry been watching too much fireman sam)

[schtall]

This might sound daft...is the actuator the correct one in the correct position ? The rwd has an almost identical turbo but the actuator rod is 180 out of phase (if that makes sense)

Interesting, I'll get a photo of mine, do you have a picture of what it should look like for reference please?

[schtall]

Also as (from a quick read) it can be caused by blocked dpf...(you said yours has been removed)...After the dpf there is a openy closey valve thing in the exhaust pipe. Have you checked that that is able to do its thing ? (Sorry been watching too much fireman sam)

I didn't notice a valve in the exhaust, but I have checked the DPF pressure reading in the Forscan data and it is minimal (<10kPa).

[sherwoodcycles]

I'll check that I'm nit thinking of my vivaro with that exhaust valve.......I'll take a photo of my turbo actuator rod thing and post it

[sherwoodcycles]

Here are pics of the turbo and actuator. The loom plugs into the bottom and shouldn't be twisted. If you unplug the loom and the plug seems 'upside down' then that would be an indicator too. But checkbon the rod pisition and the position of the rod actuator in its resting position

[sherwoodcycles]

Ignore the exhaust valve. I just looked and that was on my vivaro

[schtall]

Here are pics of the turbo and actuator. The loom plugs into the bottom and shouldn't be twisted. If you unplug the loom and the plug seems 'upside down' then that would be an indicator too. But checkbon the rod pisition and the position of the rod actuator in its resting position

Thanks, that's useful. Mine looks very similar

[sherwoodcycles]

I put a thread on here somewhere about replacing my actuator as I was having starting problems and warnings for an engine malfunction.
I thought it was because of the gears in the actuator it's self being so worn.......but the problem returned
I found that wiggling the main loom sometimes stopped it. After cutting the loom open and following wires, I discovered it was the plug to the egr at fault. Once I unplugged it, its been fine. I believe the turbo actuator shares signal wires so the damage in the plug/egr valve was probably shorting out that data or confusing it. It's just another avenue you can check.

[sherwoodcycles]

I have a spare genuine actuator too if you wanted to try a different actuator