VW Touran TDi (168 bhp version) - VW Turbo Diesel fault

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Tue 3 May 2011 19:46
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - Touran Owner

Vehicle has only done 45,000 miles and is justover 4 years old. About a year ago, it started playing up; the warning light (the one looking like a coil) would flash, the warning chime sounded and the car went into (I suppose) limp home mode. This happened from time to time and was temporarily solved by pulling over, turning the engine off and restatrting which seemed to reset whatever was wrong. It got worse (more frequent) a month or so ago, and my local engineer fitted a new turbo. All seemed OK until it happened again three time last Saturday morning. The fault says something like "boost pressure outside range" I guess that the turbo being brand new, the problem must lie somewhere else. Does anybody have an bright ideas or good advice?

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Tue 3 May 2011 20:01
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - Collos25

Maybe the EGR valve requires cleaning.exactly the same problem on cousins Audi same engine agent wanted to fit a new turbo at megga cost the local injection specialist cleaned the EGR and various pipes cured the problem not saying its the same fault but worth a try.

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Tue 3 May 2011 20:37
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - unthrottled

"boost pressure outside range"

This could be the ubiquitous overboost problem which causes the ECU to limit fuelling to prevent the turbo from overspeeding. You need the exact fault fault code. I'm asuming the 'engineer' did verify correct vane operation before declaring the original turbo dead??

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Tue 3 May 2011 20:47
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - Collos25

I very much doubt it.

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Tue 3 May 2011 20:48
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - Collos25

I very much doubt it.

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Wed 4 May 2011 10:04
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - Touran Owner

Thanks for the response - the VW fault code is 00665 (apparently, it has a generic fault code equivalrent of P0299) "Boost pressure regulation control range". I don't know whether that helps... ...

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Wed 4 May 2011 10:09
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - Touran Owner

Oh, yes, regarding the previous turbo, he removed it, cleaned it up and checked it out and found a faulty wastgate actuator. He said he tried to get that specific part without success and had to go for a new turbo - got one from TurboTechnics in Northampton for £550 rather than VW at probably three time the price. He is normally pretty good and has a good reputation locally; we've been using him for years. It could be that his knowledge of turochargers isn't the best...

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Wed 4 May 2011 10:51
VW Touran TDi (168 bhp version) - VW Turbo Diesel fault - dieselnut

Sounds like your mechanic hasn't got a good enough code reader for VW. You need either Vagcom or VCDS or of course the one VW dealers use.

That will tell if the ' out of range' turbo pressure is either over or under pressure & that is important in deciding where to look next.

Its amazing how people go for one of the most expensive parts to change without properly knowing what the fault is.

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