Hi all,

 

Trying to diagnose why my fuel economy has dropped significantly along with performance.

 

I've cured sticking vanes with mr Muscle and some careful wiggling along with some good hard runs.

 

I've got fuel + air filters ordered as they need doing soon anyway.

 

I'm only getting 30-40mpg where I used to be getting 50-60 on a good day.

 

I've plugged in Torque Pro and no issues reported. Not had chance to grab my laptop with VAGCOM installed yet though.

 

My best guesses are MAP/MAF sensors. Can anyone provide any insight how to check these in VAGCOM/VCDS using the measuring blocks?

 

Edit to add: 1.9 ATD PD100 engine

Edited 30 December, 20169 yr by FollowingGhosts

I would look at the temperature sensors for fuel and coolant as well, they're notoriously inaccurate after a few years. MAF is a good shout though, MAP not so much, they're generally reliable.

MAF and MAP seemed to be fine. (Expected pretty much matched actual)

 

Fuel temp sensors and coolant temp sensors seemed to be reading fine as well.

 

No error codes logged. Anything else I can checked?

Is your brakes ok (binding)???

Is your brakes ok (binding)???

 

I thought the same thing when reading the original post, some times the simple things are overlooked!

Fairly certain the brakes aren't binding, but I will check when I drive back later.

 

I've swapped the air filter (it was filthy) and the fuel filter (it was about 3x heavier than the old one and black inside) and the car seems to be driving much better for it. I've gone from getting 40mpg if I'm careful to 47 if I'm hoofing it which is about normal where I live given it's also winter.