MPG has gone down in my diesel - any ideas ?

Post by **lhd** » 26 Sep 2006, 08:42

I changed my fuel filter for the first time in two years,

Which seems to have made a difference.
It was pretty clogged up with crap, and seems a lot smoother with better mpg.
I'm not sure if it's in my head, but it does feel better....

lhd...............

Post by **ringo** » 26 Sep 2006, 11:49

thanks - i might try that!

Post by **Simon Baxter** » 26 Sep 2006, 18:33

Whoever said that they are getting 50mpg from their 1.7 forgot to say that it was being towed the most of it.
In the real world, 30-40mpg. If anyone says they are getting more they can't do maths or are lying.

Post by **rogbodge** » 27 Sep 2006, 21:09

The air intake duct runs up the vent cavity & terminates as I recall in a rearward-facing inlet cowl - this arrangement generally keeps rainwater out of the engine air feed - surely a good idea?!!!

I've thought of replacing my duct with industrial / automotive flexible ducting - eg Enduraflex TPE 400 STD - said to come in 10m lengths it has a temperature performance up to 135 deg C, and I'm only assuming that it will deform into an oval section to sleeve onto the air filter's plastic cowl.

I routinely get 40 mpg from my 1.7 KY diesel, without the gentlest of right feet!

Post by **Simon Baxter** » 27 Sep 2006, 21:56

If the MPG has gone down then, the price of fuel has gone up!

Things worth checking but no one ever does.

Tappets (no they ain't hydraulic)
Cam timing.
Pump timing.
Injector spray pattern.

as well as the routine filters etc.
Brakes not binding.
Tyres done properly.
Wheel alignment correct.