A4 B5 115bhp poor fuel economy

[gorillamonsoon]

Hello all

This really is a great forum. I've been using it for a while but now I need to post in the hope someone can help with a problem I am having.

My 2000 A4 really is my pride and joy. It an A4 B5 saloon with a 115bhp PD engine. It has seen me through to 190k miles and I can honestly say it has never missed a beat (the odd MAF meter replacement aside!)

Anyway, a couple of weeks ago I had the timing belt and tensioner replaced by my local independent Audi specialist (Lion Garage - Leicester). They also advised I change the fan belt tenstioner which I gladly did.

My problem is that now the vehicle is returning c.10% less fuel economy than it did before I had the belt replaced. Before, I could comfortably get to 650 miles on a full tank - now i struggle to get to 600 miles.

I haven't been back to the garage yet but I would really appreciate if anyone has any ideas why this is. With the price of diesel these days together with the fact I cover over 600 miles a week means this is an expensive problem which needs fixing

Could this be a problem with the belt not being correctly tensioned? There is no difference in the car's performance, its just a lot thirstier than it used to be. Like I say I want to take it back to the garage this week and it would be good if I could go back armed with a better understanding of possible causes.

Any help would really be appreciated

Thanks!

[paul b]

Do you have VAG-COM? I have heard there is some special codes to do with the timing belt replacement, so maybe you could do with having a look at that. Hopefully my own VAG-COM cable will arrive soon, so I can do the same on mine, though I haven't noticed a problem yet. There is the chance the timing could be ever so slightly out, you'd have to see what the computer says. I take it that it's been serviced regularly, i.e. air filter, oil, oil filter, fuel filter, pollen filter etc?

Paul

[gorillamonsoon]

Hi Paul

Thanks for your post. If anything my car has been over-serviced i.e. oil and filter changes every 3-6 months. I've always used good quality oil also (recently been using Lucas Oil Fully Synthetic with oil stabiliser).

I don't have VAG-com but I rang the garage today and they're happy to do a diagnostic to see if it shows up any problems. Interestingly, I mentioned I thought it was a problem with the timing (as this problem only materialised after I had the belts changed) but he "doubts it will be a probelm with the timing belt"

Anyway, the car is going back to them on Friday and I'll let you know what it turns up

Thanks again

[gorillamonsoon]

So i took it to the garage that changed the timing belt yesterday and they could not find a fault with it. The hooked it up to a diagnostic and it turned up no faults i.e. the timing, according to the diagnostic was OK.

Not sure where to go from here. i'm thinkning I'll give it a week before giving it a full service to see if that makes a difference.

On reflection, another difference to my car now is that it doesn't start as easily as it used to (prior to the belt being changed). it chokes a bit before sparking into life. i told the garage that changed the belt about this but to be honest, I have lost confidence in them.

Any help would be greatly appreciated.