Volkswagen Passat TDi - VW Passat Head Change problem

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Fri 1 Apr 2011 12:38
Volkswagen Passat TDi - VW Passat Head Change problem - Jamesiecotter
Hi there

Had a new head fitted to my 2001 VW Passat 130 TDi Sport last year and ever since then it's been really heavy on fuel and doesn't start as readily as it used to. I used to be getting high 40s on my commute to work and it's now mid 30s and that's with me totally changing my driving style and driving like a granny. Theres no loss of power or any other symptoms apart from the occasional black smoke cloud if i nail it. It's been back to the garage that done the work twice and they've said they can't find any problems. I took it to another independent VW specialist who told me it was the coolant temperature sensor, charged me £50 and gave it me back with the same fault!

This morning I received a Vag Com lead and was having a nose about, just following some things off the net, and there were no fault codes listed but I discovered the cam timing is running at -4.4 and if what I have read is correct it should be between 0.0 and 0.5. I spoke to the garage that fitted the head and they said they've checked, checked and checked the cam timing again and it is correct but he did admit they do it manually not with a laptop. Am I right in thinking this could be causing my problem? If not could anyone give me any advice on anything else it could likely be?

TIA

Jamie
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Fri 1 Apr 2011 13:56
Volkswagen Passat TDi - VW Passat Head Change problem - Roly93

Yes, this would account for all of these symptoms, they may still have the cam belt a notch out of place I'm afraid assuming this is a PD engine which I think it should be.

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Fri 1 Apr 2011 18:29
Volkswagen Passat TDi - VW Passat Head Change problem - Jamesiecotter
Thought as much :-(. The thing is I suggested the belt being a tooth out as soon as the problem arose (pretty much as soon as I got the car back) and was told that if the belt was a tooth out the car wouldn't run, which I know to be untrue. Spoke to the garage again just now and although they are adamant there's nothing wrong with the timing they are having the car in again in two weeks so I'll update after that.

Cheers for the reply Roly much appreciated mate :-)
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Mon 4 Apr 2011 23:54
Volkswagen Passat TDi - VW Passat Head Change problem - Big John

Being one tooth out can cause major issues. I struggled with a capri 2.0 pinto auto many years ago that was one tooth out after a recon engine was fitted. Economy was awful, performance was weird (initial torque OK - poor at higher revs) and once when I stopped and lifted the bonnet when frustrated with it I found the exhaust manifold glowing bright red! Eventually double checked the cam timing and reset - what a difference!

The extra performance/economy only lasted 6 months though, as well as misfitted cam belt the recon engine had not been fitted with a new hex oil pump drive shaft which showed itself at high speed on a motorway when it rounded. Couldn't stop the engine quick enough as the auto box kept re-starting it.

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Tue 5 Apr 2011 10:32
Volkswagen Passat TDi - VW Passat Head Change problem - injection doc

most diesels have a tapered camshaft sprocket, so you can set the cam up with a tool or dial gauge and then tighten the sprocket to the cam when the belt tension is correct and then recheck. It doesnt have to be a tooth out ! infact a tooth out normally represents about 10-12 degrees depending on the size of sprocket and number of teeth

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Sat 23 Apr 2011 21:38
Volkswagen Passat TDi - VW Passat Head Change problem - Jamesiecotter
Sorted! Went from -4.4 to 0.5 and the fuel economy is back to normal and the hot start problem seems to have disappeared. Thanks for all your advice chaps much appreciated
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