check if their is a crack in the rubber underneath the fray and that would explain excess fuel usage. If its frayed its probably best to replace it anyway.
Could be a boost leak, but a severe one will again cause it to run crap being lean under vacuum and rich on boost, sometimes really bad on cold start due to the lean problem, but if you've got hoses, swap them over and see how that goes first
Update, no major boost/vacuum leaks. Got the BOV replaced, upper intercooler hoses replaced and the o2 Sensor replaced. Apparently the Air Temp Sensor sensor was reading 70degree temps, after a good clean its now registering 50degress, unsure if this is norm/high.
They are gonna reset the ecu for me before I pick it up as well. So heres hoping..
Power is better, unfortunately, fuel is still crap, a touch above a quarter of a tank and only done 210kms. So given what i've already fixed, what would be next on the list?
Since the ECU was reset, how long does it take for it to come out of "learning/limp" mode, do I need to do another full tank now to get a proper comparison? Cheers
I usually get about 160km to last quarter tank till fuel light comes on so wait till the light before u get too worried bout economy u might be supprised
nah thats pretty bad even I get 14L and I have a pod filter sucking in hot air which cant help. dont have time to read all pages did you change o2 sensor? Cause... I just replaced mine got 12.6 L / 100km tank involved lots of spirited hills drives (100km) highway (50) the rest city. not a normal tank (mostly all city and I got 14L) O2 sensor $100 delivered.
edit: total tank was 434.3km and filled up 54.75L had fuel light on for 20km perhaps more.
O2 sensor already done and ecu reset at the start of last tank. No boost/vacuum leaks. Leads/plugs/injector seals and fuel pump next up. Any of these noticeably effect fuel economy.
After swapping the AFM out with another one (Cheers by the way Brackenridgevr4)), now getting 350-370kms from 46l, so much happier with this. Car is currently in the workshop getting the following done:
Check/Clean Idle Stepper Motor
Check/Replace Throttle Positioning Sensor
Check/Replace Engine Coolant Temp Sensor
Check/Replace Knock Sensor
Boost/Vac Leak (Compressed Air)
Engine Leads
Rocker Cover Gaskets/Throttle Body Gasket/Intake Manifold Gasket and Engine Oil Top-up/Flush
Spark Plugs and Spark Plug Seals
Injector Seals
Fuel Pump (under back seat)
Fuel Filter (engine bay?)
Fuel Filter (under the fuel tank. drives side rear door under the car.)
3SX Fuel Rail Loop
Transmission Cooler (Mounted behind VR4 Emblem)
Front Mount Intercooler (With Power Steering Cooler between AC Condenser and FMIC)
Bleed Valve @ 10psi (Factory solenoid pipe needs blocking)
Apparently the front bank of Spark Plugs were horrendous and the Rocker Cover finger tight in most places, Gaskets and Injector seals were rock hard.
Dread to think what the rear bank is like..
Turbo Y pipe has a fair bit of oil it in so its suspected one of my Turbos is on the way out.. (Noticed the upper intercooler pipes were quiet oily when replaced as well). What is a second hand replacement turbo worth?? the workshop has lots of spare
parts from a Legnum they wrecked for somebody last year.
After this its Full Exhaust and Tune by Steve (i'm hoping), got the 3-Port ready to go in as well. Can't wait to see how shes goes after this recent work.