Hi,

I am new here. I have Skoda Octavia 2.0 TDI 150bhp 2015 reg.

It has some mileage on it but I was nearly doing 600 mile per tank before and now the fuel light comes at 360 and barely makes 400.

Had new timing belt.

Full service.

Throttle looks clean as I opened it.

Had a Diesel Clean as well. 

Clutch looks ok.

New tyres.

I have a OBD Eleven but I am struggling to use it for the purpose of fuel economy.

Anyone can help?

Thanks

Luis

Timing belt replaced before or after the drop in MPG?

Edited 21 December, 20241 yr by J.R.

When I bought it it was very easy doing 560 Miles to tank (I fill tank full). After about a year it dropped 490ish per tank.

I changed fuel injectors because they were leaking but nothing changed. 

I then did timing belt soon after and car was still doing same around 490 with careful driving. I have done 20k since timing belt and after doing service this summer everything went downhill. I am lucky to do 420 per tank. I had fuel light come at 340.

So Timing belt change was not the cause from looks of it. 

 

Thanks for reply. 

My vehicle was like that when I bought it but I did not know any different.

 

I cleaned out all the clag and schmoo from the throttle body because the engine was shaking on shutdown, I was fearful it might be the DMF so started with the easier cheaper possibilities, the throttle venturi was severely restricted and the car was far more responsive afterwards and the fuel economy increased significantly.

 

I have since stopped all EGR by fitting an emulator/simulator, I've done 60K miles since and no drop in performance or economy, one day I will look with a borescope, I dont expect to see any schmoo.

 

As yours is a gradual drop in MPG it would be my first port of call.