125tdi woeful fuel economy, help!

[gldgti]

The fuel pressure won't likely show any problem, unless it was low, which would seem unlikely.

[ZokEE]

Yeah, max fuel pressure 26580 psi, max MAP 36.7 psi.

[gldgti]

Yeah, max fuel pressure 26580 psi, max MAP 36.7 psi.

That 36.7 psi was a spike right?

I dont think the stock boost is that high - should be below 30. It will certainly spike under the right cercumstances, but I reckon it would be plateau-ing around 25 IIRC.

***EDIT*** can you confirm the MAP as gauge or absolute?

[ZokEE]

That 36.7 psi was a spike right?

I dont think the stock boost is that high - should be below 30. It will certainly spike under the right cercumstances, but I reckon it would be plateau-ing around 25 IIRC.

***EDIT*** can you confirm the MAP as gauge or absolute?

Can't say, that was just the maximum it logged. I had the laptop on the passenger seat and not watching it while going. Hopefully tomorrow I'll get a good go of it minus kids and other distractions.

[h100vw]

Not forgetting, if you are logging with VCDS that it adds ambient pressure which needs to be subtracted.

Gavin

[ZokEE]

36.7 psi absolute map, so 22 psi taking off atmospheric pressure.

[Mysticality]

My MAP consistantly reads 1.01bar over boost (about 14.6(?)psi), but my phone will only read up to 22psi before it won't show any higher. Proper boost gauge plumbed in shows actual boost to be up to 30psi, but this is revo stage 2.

[ZokEE]

So my problem is fixed....

By itself.....

After driving the 1400 km to cairns to be told nothing is wrong with the car.

Literally a few hours before I reached cairns the long term stats flicked over 99 hours 59 minutes and reset, so when the service department looked at it it was reading long term average of 5.5 L/100 km, not the 10.6 it was reading when I left home.

Service department could not fault the car. I provided them with evidence of 7 tank fills of 11.5 L/100 km and was told this was acceptable. Salesman who sold us the car has been brilliant, said that was crap and said to go and do some urban k's for another average.

Filled tank and drove round cairns for the afternoon, clocked up 150km driving like I stole it, went and refilled and the ****ing thing returned 8.8L/100km.
now driving home and the distance to empty is like 900 k's on a full tank, long term average on mfd is 7.6 L/100 km after about 400 km of mixed highway and hill climb thrashing (gillies range/highway if anyone is familiar).

Glad in one regard, completely pissed in another.

Just spent 5 days and god knows how much on accommodation and food and fuel to have it working properly but no idea why!

Thanks to all who posted ideas and advice previously. I'll see how it holds up once I get it home.

[gldgti]

Wow, that's bittersweet for sure!

[Sword_Dude]

I must admit I have been pretty impressed on the fuel economy on mine even though we have only done about 500km. We are getting long term averages at around 7.5 by the display with mostly urban driving.