Passat Diesel Problem

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Fri 20 Jul 2007 10:11
Passat Diesel Problem - Glaikit Wee Scunner {P}
Passat 100ps Estate PD TDI. Mileage 99,000 plus.

On the way to work today I stopped at some road works and because a long wait was anticipated I switched off the engine.
When I set off after 10 minutes, the engine power was low and car barely could get up the hill. No warning lights displayed.
I pulled over and stopped and switched off. I did that several times with no luck. Set off for work and noticed the mpg instantaneous display was only reading in low 30s mpg- much lower than usual. No clouds of smoke from exhaust. After a couple of miles power came back to normal.

Is this symptomatic of MAF failure?
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Fri 20 Jul 2007 10:26
Passat Diesel Problem - 547HEW
As there is no excessive smoke, and mpg indication is poor, I think your engine has briefly gone into limp home mode, where injection timing and boost is backed off to protect the engine from damage, or giving excessive emissions.

If this is the case we may assume that a vital sensor has briefly gone down, possibly ECT sensor?

In any case I think you need to get the DTC's read (Diagnostic Trouble Codes) - VAGCOM is the most cost effective.

Hope you get it sorted
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Tue 24 Jul 2007 21:33
Passat Diesel Problem - sinbad
Hello mate my friend had the same problem with his 01 Passat tdi. He had the MAS sensor replaced but still same problem it eventually turned out to be the catalyst which had become loose in the exhaust system and was blocking the release of gases, hence causing power loss especially uphill. Get a mechanic to check your exhauast system especially the cat.

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Mon 30 Jul 2007 14:24
Passat Diesel Problem - Glaikit Wee Scunner {P}
Car has run fine since the incident 2 weeks ago.
Got connected to the diagnostic thingy which reported a fault suggesting the intake trunking had been blocked.Nonsense of course, so I guess that a sensor gave a wrong input for a short period.Trunking, MAF etc was checked out and no problems seen.
Cost me £53 at a VW independent to find that out.

Hope I do not go into limp across France next week- that would be fun.

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Mon 30 Jul 2007 14:30
Passat Diesel Problem - Screwloose
GWS

What was the fault code number? That's a very odd code description.

An oil-fouled MAP sensor would be more likely.
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