Tb48 worsening economy

[Skitzyrex]

Hi All,
Have owned my 07 GU 4.8 for about 7 years now and the economy has gone from around 21 lph around town to between 26-28lph. Car has now done 210000 kms.
Now there’s no engine lights coming up to indicate an AFM or O2 sensors are faulty, could they need replacing without engine lights? Also could the valves affect the poor economy?
Thanks for your input

Mick

[Skitzyrex]

No one? [emoji51][emoji51]

[Avo]

No one? [emoji51][emoji51]At a guess as no one has commented, injectors

Sent from my SM-G930F using Tapatalk

[Clunk]

Yes Valve clearances can affect fuel consumption, so can dirty MAF sensor and air filter.

What have you done to it in the last 7 years? Addition of accessories etc

[drgtr]

Clean your Air Flow Meter with CRC contact cleaner so it doesnt leave a residue.
Also Replace your oxygen regardless as they start to fall off the operating range with age and wear and tear from the heat.

One over seen thing is also change your coolant temperature sensor as that can return incorrect readings and make the ecu run the car rich.
Also replace your thermostat. It could be slightly stuck open and car is running cooler constantly which makes the car drink more fuel too.

[Skitzyrex]

Thanks gents, I’ll work through those things. I’m fairly onto the maf sensor and have cleaner for it so do it frequently.
Clunk, as for the accessories, if anything I’ve made it lighter.

Thanks again