15mpg
 

i thought there was something going wrong over the last couple of months, after only getting 38mpg around town, today it dropped to 27 miles to a tenner, it started to missfire bad, i had to drop it into 2nd gear and keep the revs up to get home, i'd already changed the fpr, but looking at the fuel pressure guage it was reading 60psi:eek:, so i had the ball ache of changing the rail yet again, on doing so the fuel pressure has dropped to 37psi:) , i'll see how it goes on fuel now.

lol the fuel pressure regulator has to be one of the most common things to go on the s12. :rolleyes:

really does suck to change it too, glad I have an FSE to go on

Mine has very similar symptoms and since I put the new head on it doesn't like to tick over, I thought it was a dodgy injector I now wondering if it's the fuel pressure regulator.

fit a inline pressure reg mate.

So fitting something like This or This may cure the problem?

bum. sold me car cos of the poor fuel (and ridiculous insurance) and it could have been this :P why didnt I find out this before :trout

Although the wideband showed it as lean on tick over, even crusing at 30 so about -10PSI boost she was reasding and AFR of 13.something i.e. a touch rich :(

My c02 is all over the place on tick over at the moment.

13 is lean mate, i would not run an engine in the 13's on boost:eek: , i'd say about 14's on tickover, although my mk1 din't like to tickover that lean, i think it was an airspeed issue due to the large throttle body and big tubby, but once it was moving it was ok, i got it mapped as lean as i could at 70mph untill it started to misfire, then put some more fuel in, it did around 32mpg on a long run.

minus 10PSI i.e. not on boost, just crawling. For some reason the best I ever got from her was 20mpg and pushed you could get that close to single figures.

Srukk sge gas gone now so nothing much I can do about it :trout