EFI Fuel pressure too high?
 

Hi ppl, just fitted myself a fuel pressure gauge to my 1.8 EFI ZVH after suspecting for some time the fuel pressure was wrong.
With reference pipe disconnected it reads about 3.5 bar. Am I right in assuming it should be 3bar as that's what the injectors (701s) are flow rated at?

Now about a week ago I noticed the car felt quite a bit quicker than usual, on popping the bonnet I could see fuel leaking out of the pressure reg. adjustment screw.

This was because it was nearly fully unscrewed, ie leaving me no room at all to lower the pressure any further.

Is it possible the regulator's gone faulty?

Surely it doesn't matter what fuel delivery pressure is from the pump (walbro 255l/h), just that the regulator does it's job?

Any ideas welcomed......as are any offers of a free working regulator... hehe.

Thanks, Karl.

Change the regulator yesterday, if not sooner.
No fuel should leak out, the diaphragm inside is split, this is why it is acting funny and overfuelling.
There is a diaphragm inside one side of which is open to the inlet manifold pressure via the vacuum pipe, the other side of the diaphragm is a valve that raises/lowers in a orifice to alter the pressure, so when you put your foot down and vacuum depletes the fuel pressure goes up, when crusing along on a light throttle with high vacuum the reg goes thr other way and lowers fuel pressure to it's base setting so you get a weaker mixture saving petrol.
tabetha

Thank you very much for the information Tabetha. I shall of course follow your advice :)

Off sourcing I go....

Just noticed your addy, I was at cayton bay from 13-20 sep, noticed a few cars hanging out by cafe's near the old swimming pool bit/peasholme park.
tabetha

Hehe yeah they're the usual hangabout places for us lot up here...

Next time your in this neck of the woods gimme a shout..always nice to put a face to the name etc :)