I'm hoping its the LPG injection which is causing my diesel usage to drop a bit too. Have kept to the same strict use of Millers diesel plus, but now with the added use of lpg (vaporised) injection once boost reaches 3PSI. I'm thinking now the car may have learned that there's some alien fuel being injected and its trimming off diesel injection a little bit when accelerating under fairly heavy load. I got 58mpg on my commute to work this morning which is my best yet. And on the Jurassic run (Chris Ellis will testify I wasn't dilly dallying all the time ) I got a smidge over 50mpg for the whole day.

Very impressed now. Just need something "mega" to really use the lpg how I feel it was intended.

How much lpg do you get through with the injection system?

Chris

How much lpg do you get through with the injection system?

Chris

Well, my gauge is still reading full. I guess boost on a TDI doesn't really go over 3PSI all that often. Under slow cruising and coasting its basically just above 0. If the tank stays full for too much longer I might nip out and whip the pipe off to check its still injecting. It certainly was when we faked the regulator with 5 PSI using a head gasket testing kit.

I've seen figures batted around of 3000+ miles to a tank of propane, but that might be with a huge tank and I have only a small one in my spare wheel well, and I did fill it totally to max pressure on its first fill-up to ensure it was tight and secure at maximum load.

I think you need to work out the true cost per mile. Diesel + Millers + gas

I don't bother with Millers (at the moment).

The saving with LPG is VERY dependant on how you drive, if I make excessive progress the LPG lasts a few tanks of derv (about 4ish).

If I drive like I usually drive, which is to make progress without overdoing it on acceleration, I can run a few months on a single LPG fill-up (which costs about a tenner).

Derv wise (again depending on how hard the car is driven) I tend to get around 50-70 miles/tank more range.

Although I reckon I'm saving roughly 2-3p/mile based on fuel cost, my install cost me around 2k so that's a LOT of miles. Never going to recoup that cost realistically.

I know the millers Vs no millers is a no brainer, as the millers costs me about £8 a bottle, but my mpg saving on diesel using it, is around £30 per bottle. Factoring lpg into the equation is so tricky I'm not going to bother. Its very marginal I would say.

If my lpg usage doesn't go up much more I might turn it down still further to cut in at 2psi or something damn low, and then mayb tweak the injection rate half a turn too.