Poor fuel economy - 6L manual

[exanVZ]

I've had this car for nearly 8 years and been on the same tune for about last 7 years, previous I used to get between 14-16L/100km and on the highway less than 10 so that's why I'm trying to work out why it's gotten so much worse all of a sudden.

 

[exanVZ]

I would book it in at the workshop I usually take it to but they're booked out and busy till basically March/April so not sure if I should try and take it elsewhere or keep trying to work it out myself.

 

[losh1971]

Might be worth swapping the spark plugs and replacing the air filter if it's not washable.

 

[Jeda]

I've had this car for nearly 8 years and been on the same tune for about last 7 years, previous I used to get between 14-16L/100km and on the highway less than 10 so that's why I'm trying to work out why it's gotten so much worse all of a sudden.

Your brakes aren't dragging, are they?

Wheel bearings even?

 

[exanVZ]

Might be worth swapping the spark plugs and replacing the air filter if it's not washable.

Done both of those already and didn't make much difference unfortunately.

 

[exanVZ]

Your brakes aren't dragging, are they?

Wheel bearings even?

Thanks for the idea, not really sure how to test that. Maybe jack it up and check how freely they spin? Not making any weird noises and feels normal to drive. I changed rear pads and rotors about a year ago and haven't changed the fronts in a while but they probably need done soon.

 

[vc commodore]

Check for brake or bearings dragging, jack the car up so the wheels are off the ground and see if they spin freely....

Takes 10 minutes of your time

 

[Ginger Beer]

How did your plugs look?

If all else fails pull your injectors and get them cleaned and tested, when were they last cleaned and tested, cost is minimal compared to poor fuel economy

I would look at getting them cleaned every 50km

Your injectors need servicing like most parts, they get clogged up and occasionally don't seal correctly

Like this >

 

[exanVZ]

How did your plugs look?

If all else fails pull your injectors and get them cleaned and tested, when were they last cleaned and tested, cost is minimal compared to poor fuel economy

I would look at getting them cleaned every 50km

Your injectors need servicing like most parts, they get clogged up and occasionally don't seal correctly

The old plugs didn't look too bad as far as I can tell, will chuck a pic below. Can't remember how old they were but they looked about ready to change. I'll check out the wheels and brakes as suggested above and check back through my records to see if i've ever had the injectors serviced or not, might be time to clean or replace them. Thanks for the suggestion,!

 

[hademall]

It looks like your car may be running a bit rich judging by your old plugs.