MPG dived after cam replacement

[fourstardan]

I have googled this and my timing belt change might again need to go back.

MPG readings are really diabolical, it's a gradual slow rise,, I did a two hour trip on motorway yesterday and got to 50mpg where as pre cam I'd be getting high 50's. I know it's cold at the moment but it don't feel right to me.

Am I right to go back to the garage to look at this and if yes what will they need to do? Is it a full restrip and the belt being tightened or an ECU change?

I went independent for this change and I wish now I'd got VW to do it so I could at least hound them when I've not been happy lol.

[Belle427]

I'm assuming you had the timing belt changed?
Does the car feel any different to drive? ie does it lack power or have trouble starting?
What is the car/engine?

[fourstardan]

Car feels the same to drive, I do notice a bit of issue pulling away at standstill sometimes but I've put this down to road surface being wet. Maybe it isn't.

It's a B8 passat 67 plate and it's the first cam replacement I've just done.

[Paynewright]

Not clear whether you had the camshaft or cam belt changed (or both).

First check would be see if the timing marks align. If the camshaft was changed also check what was fitted.

Also, I think the onboard computers are notoriously inaccurate.

[fourstardan]

Oh sorry thick head this morning.

It was a standard cambelt change.

I'll check the alignment. Is it an obvious one if unaligned?