MAP Sensor location VW Mk7 Golf TDI 1.6 (Limp Mode)

MAP Sensor location VW Mk7 Golf TDI 1.6 (Limp Mode)

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ESPollock

Original Poster:

4 posts

79 months

Friday 6th April 2018
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I've been having an issue with my 62 plate, early Mk7 Golf 1.6 TDI for over a month now, in that the car is in limp mode with an as yet undiagnosed fault. Mileage 40K.

There are currently no dash lights on, unless I really push the engine hard, then only the flashing yellow glow plug light comes on. The car always resets this lamp on restarting the engine.

The diagnostic code thrown up by the ECU is P0229 - Boost Pressure Regulation Control Not Reached.

I've had the car looked at by 2 garages - one came up with nothing, the other suggested it be seized vanes on the turbo, however the actuator is working and manually can move the vanes so we're suspecting that isn't actually the case. I'm considering cleaning the turbo however with 'Revive' as soon as I get the fault diagnosed and fixed.

It's been suggested by a diagnostics engineer that it could be the MAP sensor that is faulty - reason for this is that unplugging the MAF results in no difference to the drive. The car is sluggish permanently, even at low speeds, below 30mph.

I've contacted VW parts to try to work out how much and where the MAP sensor is located. No-one seems too sure.

Does anyone know where the MAP sensor is on a Mk7 Golf TDI 1.6 Bluemotion? I want my local mechanic to test it, and its wiring loom, next week.

Cheers all and thanks very much for any help on this.

Krikkit

27,000 posts

188 months

Friday 6th April 2018
quotequote all
Does your mechanic not have a copy of Autodata? That kind of thing is in it.

ESPollock

Original Poster:

4 posts

79 months

Friday 6th April 2018
quotequote all
Krikkit said:
Does your mechanic not have a copy of Autodata? That kind of thing is in it.
Thanks for the reply Krikkit. I guess he may not have but I've just looked Autodata up so will bring it to his attention if need be. I've got a schematic of the part in from partslink24.com so we do have a good idea of where it might be. I was just wondering if anyone could confirm for me...

shtu

3,712 posts

153 months

Friday 6th April 2018
quotequote all
Bottom line - take it to a better garage.

It's not the vanes sticking - that gives an overboost warning, ie, "limit exceeded".

You most likely have,

- A vacuum leak somewhere.
- A faulty MAP sensor that is under-reporting the pressure.

A decent garage can TEST for these faults, not just randomly swap parts at your expense.

ESPollock

Original Poster:

4 posts

79 months

Friday 6th April 2018
quotequote all
Hi shtu - and thanks for the reply.

A smoke test of the system has been done twice, with no problems.
The better garage did that - but then they also recommended a turbo rehaul at the cost of £900, even though the actuator is working. They couldn't positively diagnose the turbo as being faulty as it's a sealed unit apparently, so this diagnosis was a process of elimination only.
That's why we're looking at the MAP sensor now. Fingers crossed...
Good to know we may be on the right lines.

shtu

3,712 posts

153 months

Friday 6th April 2018
quotequote all
ESPollock said:
The better garage did that - but then they also recommended a turbo rehaul at the cost of £900, even though the actuator is working. They couldn't positively diagnose the turbo as being faulty as it's a sealed unit apparently, so this diagnosis was a process of elimination only.
Then the first one must have been monumentally pisspoor, 'cos your better one are idiots.

Any garage with decent diagnostic kit can read live data on the manifold pressure, and drive the car or blip the throttle a few times as they do. No garage in their right mind says "yeah guv, might be the turbo innit, dunno, but it'll cost you a grand to find out if we guessed right".

Get to a garage that has a clue. Hunt around for recommendations of VW independents local to you.

mocky-2008

1 posts

28 months

Friday 1st July 2022
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did you get your car fixed in the end and if so what was it ???