MPG problems for the past year

[Agreeable Slick]

Might be temp sender related. Seems silly, but they can affect mpg. Might be worth chucking a new one of them in? £30 ish.

EGR wouldn't really effect it, as it's an emissions addition. Will drop mpg by a few points, but not by this much.

[richandhazel]

Timing might well be worth a look. I set mine at around 70 on VAGCOM and I can usually get at least 500 miles on a tank full.
Best was just over 600 but when I did that it was just running to and from work (M3 & M25) and all the roadworks were going on so 50mph most of the way!

Be interesting to know what your timing is set at

[richandhazel]

Timing might well be worth a look. I set mine at around 70 on VAGCOM and I can usually get at least 500 miles on a tank full.
Best was just over 600 but when I did that it was just running to and from work (M3 & M25) and all the roadworks were going on so 50mph most of the way!

Be interesting to know what your timing is set at

Should have mentioned........that's a 1999 110BHP, AHF engine.

[asif]

Has the timing belt ever been changed? timing could be slightly out, but i would expect performance to suffer.
All diesels seem to suffer from clogged up EGR valves, worth a look?

Timing belt has been changed at about 57k now on 80k, performance isn;t too bad but does feel a bit slower on pick up after the intercooler which I was surprised as I thought it'd spool up the turbo much faster?

[asif]

Might be temp sender related. Seems silly, but they can affect mpg. Might be worth chucking a new one of them in? £30 ish.

EGR wouldn't really effect it, as it's an emissions addition. Will drop mpg by a few points, but not by this much.

EGR has been mapped out and when the mech checked he said it's not bad as he's seen in the past so won't be the EGR

[AudiA8Quattro]

Might be temp sender related. Seems silly, but they can affect mpg. Might be worth chucking a new one of them in? £30 ish.

EGR wouldn't really effect it, as it's an emissions addition. Will drop mpg by a few points, but not by this much.

I read that EGR valves can cause quite significant running problems. It can affect the air flow readings, or so the article said.
I can't really say for sure, as i'm not really into diesels.

[AudiA8Quattro]

Has the timing belt ever been changed? timing could be slightly out, but i would expect performance to suffer.
All diesels seem to suffer from clogged up EGR valves, worth a look?

Timing belt has been changed at about 57k now on 80k, performance isn;t too bad but does feel a bit slower on pick up after the intercooler which I was surprised as I thought it'd spool up the turbo much faster?

Maybe worth re-checking the timing?

[asif]

Timing might well be worth a look. I set mine at around 70 on VAGCOM and I can usually get at least 500 miles on a tank full.
Best was just over 600 but when I did that it was just running to and from work (M3 & M25) and all the roadworks were going on so 50mph most of the way!

Be interesting to know what your timing is set at

Not sure about the timing, are there any other symptoms if the timing was out?

When I start the car from coldfirst thing in the morning it sort of hesitates a bit for about 20 30 seconds like it aint got enough revs and chucks out a cloud of smoke not coloured just like white kinda exhaust smoke as normal then stops straight away.
It's the hesitation that gets me worried kinda like the car can't breathe kinda thing (best way I could explain it )

[asif]

Has the timing belt ever been changed? timing could be slightly out, but i would expect performance to suffer.
All diesels seem to suffer from clogged up EGR valves, worth a look?

Timing belt has been changed at about 57k now on 80k, performance isn;t too bad but does feel a bit slower on pick up after the intercooler which I was surprised as I thought it'd spool up the turbo much faster?

Maybe worth re-checking the timing?

EGR is mapped out so not in use and the mech said the EG isn't that dirty anyway so hopefully not restricted at all.

[richandhazel]

I mapped out my EGR too, one of the first jobs I did after cleaning out the intake!

Have you easy access to VAGCOM, it's a very quick and easy check to see where your timing is