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Discussion Starter #1
I just don't get how people with virtually identical engine setups as mine (PP'd ACV) are regularly getting 550-600 miles out of a tank, some even more, yet mine will only do 400. If I drive like a complete wuss and it still only does 450 max. Best I ever got was 560 when it was completely standard.

I've had the injectors set and cleaned. Timing is bang on according to VAG COM. Runs sweet as a nut and super smooth. (although I have never been able to get the fuel quanitity down to the levels people mention, no matter ow I set it). It even got remapped a 2nd time to trim some of the fuelling out and stop the smoke and flywheel judder.

I thought i might be down to the weight, but I don't have any sub box or interior, seats in the back at the moment. Tried it without the 4wd, exactly the same mpg. Maybe a thinner floor would help? current got 22mm marine ply as I lug about engines and stuff and thought think stuff would just split.

Even tried disconnecting the leisure batteries to take the load off the alternator. It felt a bit better, like the engine wasn't trying so hard, but still fuel light on before 400miles on a full tank.

I don't sit at silly speeds on the motorway. usually sit around 60mph on my speedo (which is more like 67 on GPS) and try to keep it away from full boost levels when cruising. Yeah I like to give it a boot now and then, but never sustained throttle for long periods. I'm even avoiding using cruise control, and backing off up hills and making the use of carrying a little more speed down hill (free power!).

Wy last line of thinking is aerodynamics. I've got a bull bar with spots, it's raised up, and I also have a Fiamma awning and roof rack on all the time. Could that be affecting things so bad to the tune of 10mpg less that others are getting?
 

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I don't know for sure but yes ultimately it could be down to the drag (in part)

I only say this because after I lowered mine(45mm) and took the front down slightly more my fuel efficiency improved.. T:
 

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Just got 550 mile out of the 2.4D Turbo :D only used to get 500 max before i fitted the Turbo its is running Lean at the moment only getting 0.5bar max and EGT's @ 400deg max.

Always check my Tyre pressures that does make a difference , could also be down to your Type of Tyres too :confused:

Bet you would get better economy with the Front Mounted intercooler fitted ! the original top mounted intercoolers must get loads of heat soak. :eek:
 

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Discussion Starter #5
I've had 4 different sets of and tyres wheels on it, no difference.

If anything it's better on the A/T's as they make the gearing longer, so I'm actually getting 7% more than what my odometer counts.
 

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What pressures are you running in the tires?
The roof rack and awning will cause a huge amount of drag. This will significantly effect your economy.
FMIC shouldn't make too much difference to economy. I still have a top mount on my 2.5, and it does 40mpg if im carful.
Are your brakes binding, its very very unlikely, but you never know.
I assume since you have PP sorted, that you have had it on vag com and made sure all your sensors function correctly?
Do you have an aftermarket drag chute? This would really mess up your economy!
 

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Discussion Starter #8
No brake bind, wheels spin freely. in fact, it actually used to do more mpg when it had a seized rear caliper!

Will check tyre pressure. Normally run them with 60psi when I'm towing or carrying a load. In snow I'll drop em to 30. Not checked them for a while, could be anywhere inbetween.

No error codes. Never have any. just injection quantity is too high, can't get it anywhere near the paramaters.
 

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Have you taken the 7% extra mileage into consideration when calculating the MPG?

Are you still running the fuel line cooler?
and if so has that stopped it from loosing power during the longer runs?
 

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I have never been able to get the fuel quanitity down to the levels people mention, no matter ow I set it.

Wy last line of thinking is aerodynamics. I've got a bull bar with spots, it's raised up, and I also have a Fiamma awning and roof rack on all the time. Could that be affecting things so bad to the tune of 10mpg less that others are getting?
The fuel quantity thing sounds interesting...
Almost as if you've got a drag on your engine so it's requiring more fuel than expected.
Have you still got a cat in the exhaust?

The roof rack and other extras will have an effect for sure but I wouldn't have thought it'd be enough to be taking over 150 miles out of you tanks range. Certainly not when travelling at 60 mph'ish anyway.

Maybe it's a collection of several factors, but 400 to a tank does seem drastically low.
 

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Discussion Starter #14
No cat, was ditched when the Pipewerx exhaust was fitted.

No 4wd at the moment, not for the last 6 months, diff and prop is back on but still no rear shafts.
 

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No 4wd at the moment, not for the last 6 months, diff and prop is back on but still no rear shafts.
So does that mean they are still being rotated by the gearbox or have you left them un coupled?

Also what the latest with the fuel cooler?
 

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Discussion Starter #16
Yes, there is still a transfer box, prop and diff. When I had the diff and prop off it still had the trasnfer box on but with the prop flange in fresh air. even carrying 100kgs less it made no difference.

I took the fuel cooler off as the temporary bracket I'd made failed, it's all back to standard in that respect.
 

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Miles per tank is a very rough way of calculating MPG....how about your MPG figures or L/100kms. From here I would say that your tons of aero drag and the fact that in all your posts you talk about towing or hauling stuff, plus the extra weight of the FWD plus you haven't said if you have the super long 5th gear. With a short 5th and all of the above you are going to get losses. Really the rero drag is a huge factor, and the drag coefficient is gets very nasty at higher (+ 50 mph) speeds.
 

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Discussion Starter #18
With the trailer on the fuel light comes on at 360 mles!

gonna take the roof rack and awning off this week.
 

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Discussion Starter #20 (Edited)
I know, he was the inspiration behind my tyre choice, I'm running the exact same tyre.

Going to buy a new crank pulley and tensioner. Got alternator issues and mega belt slip. Just wondering if I've got an excessive current draw and it's dragging the alernator and thus the engine down.
 
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