TDI ASZ High fuel consumption, no smoke, clean logs

[t1salai]

Hi,

 

I have a bit of a problem that I am unable to solve.

 

Like out of the blue, my car started to use a hell of a lot more diesel. Motorway jumped from cca 5,5 to about 9,6 L/100KM. I drive about 140km/h on CC. Urban consumption jumped from 5,7 to a now regular 8,x L/100km. and I noticed my idle consumption jumped from 0.6/0,7 to about 0,9 without AC on and 1,1 L/h with AC on. There is no smoke, stinky diesel fumes, car drives and pulls as ever, no flat spot, jerkyness or any other signs something is wrong other the amount of fuel it uses.

 

Checked: MAF, MAP, coolant temp sensor (cluster and ECU part), fuel temp sensor, engine oil for diesel residue, turbo pipes for leaks, intake pipe for holes, fuel lines for holes, fuel cooler for leaks, scanned for errors - nothing came up. Logged via VCDS on 3rd speed pulls, all came good. Starting to loose my **** over this.

 

Didn't do: Changed fuel filter for last 20.000km and air filter for last 8.000km. Checked by brimming the tank and driving for 100km, I don't need to, I feel the consumption is greater by thinning of my wallet.

 

There are some logs in attachement.

 

Thank you for all your future help

 

EDIT: The specs of the car - GT1749VB turbo (remaped to 185bhp/400Nm), SeatSport FMIC with hardpipes and EGR delete. Other things are pretty much stock.

logovi tibor.rar

Edited 18 August, 2021 by t1salai

[sepulchrave]

There has to be a leak somewhere when the car is running, this suggests the tandem pump or the tank return pipework somewhere. Leave the car running for half an hour and lie next to it watching.

[t1salai]

I listened to your advice mate. No leaks at all. Problem is still there...

[Boyes]

Have you checked for an increase in rolling resistance, dragging hand brake etc? Something outside the engine, just a thought.

[vindaloo]

Coolant or fuel temperature sensors?