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Superb 4 cyl diesel - fuel system design fault

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I have just been checking the Superb (130PS AWX engine) over carefully before my holiday next week. As an ex diesel engineer, I gave the fuel system some scrutiny - it's simple enough on the PD engines as there are no high pressure pipes.

If you follow the fuel hose from the outlet of the fuel filter (the one in the centre of the can) it takes a roundabout route to the inlet port of the tandem pump on the cylinder head. Unfortunately, it's routed so it rubs on the underside of the charge air pipe to the EGR/anti-run on valve assembly. Mine was very badly rubbed and will soon fail.

To see all this, you have to remove the engine top cover and also disconnect the charge air pipe at the EGR valve - just a spring clip and an 'O' ring. It's a bit tight, but you can pull up the charge air pipe a couple of inches to reveal the fuel pipe with a badly rubbed spot below. There is an anti-rub mesh sleeve fitted, but it doesn't do anything and won't move along the pipe into the right place.

For now, I've put 3 cable ties around the fuel pipe at the affected point and smeared it all with silicone grease - this will have to do until after my holiday. When this pipe eventually rubs through the engine will stop because the tandem lift pump will suck air. When I get back I'll have a new angled inlet connector made for the tandem pump to eliminate the rub. (By then, the car will be out of warranty).

The engine installation on the Superb/Passat looks quite good, all pipes being clipped together - except some you can't see. I would not expect the transverse engined cars to suffer from this problem. Thanks a bundle VAG.

rotodiesel.

Thanks for the heads up. Will look at my Passat when I get home, as I have the same engine mounted the right way round also. :)

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