Drop in mpg following cambelt change...

[Type_R]

..I had my cambelt and water pump changed a couple of months ago by an Indy in High Wycombe.

Within 2 weeks of the work being done, I had to take the car back as it sounded like a tractor and they diagnosed it as having a failed water pump. So they replaced the water pump on it, and everything seemed fine.

However I have noticed that my mpg has reduced since the change. On motorway runs driving at constant speeeds on familiar routes I seem to have lost up to 10 mpg. The remapped MK5 Golf GTi could deliver up to 35 mpg on an easy going run, and my best mpg has been 40.1 mpg over 60 miles (50 mph all the way!). Now its closer to 24 mpg at best.

It seems like this might be related to a turbo pipe not being fitted back properly, causing a boost leak and hence lack of efficiency. I am not sure if this is the issue. I certainly cannot hear a boost leak but maybe it is small? The timing belt certainly does sound more noisy than in the past (when VW had changed it).

Secondly if it is a boost leak issue, does anyone know of any specialists in the Bham or London area (or between the two) that can sort the problem out.

 

[Phil W]

Has it been timed up correctly?

 

[Type_R]

Has it been timed up correctly?

I have no idea. How could one check that?

 

[Phil W]

With a timing gun/light. Most garages should have them. Take it back to the Indy to check?

 

[Maz]

Has it been timed up correctly?

I doubt this engine would run unless it was timed correctly!

 

[Frozennova]

I doubt this engine would run unless it was timed correctly!

a degree or 2 would result in poor performance rather out and out not running at all.

 

[Type_R]

With a timing gun/light. Most garages should have them. Take it back to the Indy to check?

Yeah I might just do that although as mentioned below, not sure it would run if it wasn't times correctly.

Might take it to VW and ask them to check the timing.

 

[ShakenNstirred]

Yeah I might just do that although as mentioned below, not sure it would run if it wasn't times correctly.

Might take it to VW and ask them to check the timing.

you'd be surprised how far out they can be and still run

 

[bledd]

I doubt this engine would run unless it was timed correctly!

My brother's Corsa had jumped about 3 or 4 teeth and it still ran. Sounded like a bag of spanners, but it ran

 

[Frozennova]

Its no different to using a vernier pulley with after market cams in the real world. Although not as easily changeable.

 

[Brookert]

+1 timing out, pulleys probably weren't matched up right.

 

[red eye]

Yeah I might just do that although as mentioned below, not sure it would run if it wasn't times correctly.

Might take it to VW and ask them to check the timing.

you might also want to check it the timing marks line up before you pay to check the ignition timing, what engine is it?

 

[The Edge]

My 944 had been a tooth out for goodness knows how long. Now its right it's like a differant car.

If the belt has been changed and it's worse since, you have to question whether the pulleys have moved. It shouldn't happen but it does.

 

[Type_R]

2.0 TFSI AXX with stage 1 remap

 

[s0ck]

VCDS lite might be able to tell you if the timing is within spec. It can do it for the older dervs, dunno about the tfsi...

 

[red eye]

2.0 TFSI AXX with stage 1 remap

ok the cams don't have timing marks it uses pins you can get away with 6mm drill bit. I used to make my own marks on the crank I can't remember if the had marks. Fun engine to do timing belt on tho the belt slips on the crank while you try to get the belt round the engine mount so I'm guessing the timings out by a few teeth