fault code p0234 loss of power

**iali001** · 28-03-2010,12:32 PM

hi, i have a vw passat 2.0 140 tdi se

only had it for 1.5 month
since i had oil and oil filter done i have had problem with loss of power.

1st it completetly lost power , i was told by local garage that the intercooler pipe had come off. put back on and hey presto sorted.

now again 5 days on the trot especially on motorways
the car glow plug light comes on and says engine fault and i have a loss of power

when i park up i switch engine off then restart after a minute and it is back to normal

my mate has vagcom software , he linked it to my car last night and it came up with fault code p0234 turbo boost exceeded. please help someone as i have already had a sensor and fuel filter changed on it , it was ok for 2 days then again the problem started.

**martin1810** · 28-03-2010,02:44 PM

Thats not the usual vag-com code. You should have got the 17965 code. Overboost can be the Manifold Absolute Pressure sensor or N75 valve but is usually stuck turbo vanes that need cleaning.

**iali001** · 28-03-2010,04:38 PM

hi thanks for the reply

how do i clean turbo veins ?? and how do i locate them??

**martin1810** · 28-03-2010,06:23 PM

If you need to ask, you probably need to take it to someone. The vanes are inside the turbo which means it has to be removed to be cleaned properly. If you google vnt turbo vanes...you will find lots of information.

**billcoleman** · 01-04-2010,01:09 PM

Today I had what sounds like a very similar issue. I was just starting to accelerate up a dual carriageway then suddenly a loss of power, emmisions workshop message and the glow-plug light came on. The car appeared to have switched into a "low-power get me home mode". So I pulled-over, switched-off and re-started the engine - no more lights and all was normal.

I will connect my vag-com later today and see what the error message was.

I must admit that if this had happened while overtaking - it would be pretty hazardous.

**billcoleman** · 01-04-2010,05:06 PM

Just checked my fault codes and have the following result:

16618 - Boost Pressure Regulation: Limit Exceeded (Overboost Condition)
P0234 - 006 - Short to Plus - Intermittent

I guess I will need to check/clean the turbo vanes.

**martin1810** · 01-04-2010,08:10 PM

Overboost is often sticking turbo vanes. Manifold Absolute pressure sensor or what was the N75valve is a possibility. (On the b6 passat the N75 has become one unit for all vacuum controls.)

**jamez_mk4** · 13-07-2011,08:31 PM

hello there i work in a reputable indapendant garage and have the same fault code of p0234 on a passat 2006 2.0 tdi how ever at the end of
where it says about boost pressure regulation it also says short to power intermiten so shorly this is an electrical fault? or is that just a generic sentence? so basicly does everybody else get short to power at the end of their code? thnks in advance people been ripping my nuts off over this one

**martin1810** · 14-07-2011,11:29 AM

16618
P0234
Boost Pressure Regulation, Limit Exceeded (Overboost Condition)

It doesn't include a comment about short to power. If you are using a generic scanner like snap-on, they often report the wrong details.

**jamez_mk4** · 14-07-2011,03:51 PM

Originally Posted by martin1810

16618
P0234
Boost Pressure Regulation, Limit Exceeded (Overboost Condition)

It doesn't include a comment about short to power. If you are using a generic scanner like snap-on, they often report the wrong details.

can i contact you regards to trouble shooting with this car ive checked the actuator /vacum pipes/new valve block/ the fault only occours after around 70-80 miles of driving then everytime the customer flicks the key on and off it goes for a very short period its very arkward as ive not had alot of troubles with vag tdi engines therefore i have no live data stored