Technical help Q & A Got A technical problem with you car? Keep it in here where the techies hang out and we will try to solve it for you!!

EFI Fuel pressure too high?

Thread Tools
 
Search this Thread
 
Old 29-09-2008, 10:20 AM
  #1  
cabbykarl
I'm Finding My Feet Here Now
Thread Starter
 
cabbykarl's Avatar
 
Join Date: Nov 2004
Location: Scarborough, N. Yorks
Posts: 132
Likes: 0
Received 0 Likes on 0 Posts
Default 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.
Old 30-09-2008, 07:18 AM
  #2  
tabetha
BANNED
BANNED
 
tabetha's Avatar
 
Join Date: Jul 2006
Location: uk
Posts: 24,596
Likes: 0
Received 3 Likes on 3 Posts
Default

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
Old 30-09-2008, 12:42 PM
  #3  
cabbykarl
I'm Finding My Feet Here Now
Thread Starter
 
cabbykarl's Avatar
 
Join Date: Nov 2004
Location: Scarborough, N. Yorks
Posts: 132
Likes: 0
Received 0 Likes on 0 Posts
Default

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

Off sourcing I go....
Old 30-09-2008, 01:38 PM
  #4  
tabetha
BANNED
BANNED
 
tabetha's Avatar
 
Join Date: Jul 2006
Location: uk
Posts: 24,596
Likes: 0
Received 3 Likes on 3 Posts
Default

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
Old 30-09-2008, 01:51 PM
  #5  
cabbykarl
I'm Finding My Feet Here Now
Thread Starter
 
cabbykarl's Avatar
 
Join Date: Nov 2004
Location: Scarborough, N. Yorks
Posts: 132
Likes: 0
Received 0 Likes on 0 Posts
Default

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
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
JK12
Pictures, video & Photoshop Forum
33
26-04-2021 12:09 PM
155lee
Ford RS Cosworth Parts for Sale
19
27-10-2015 04:55 AM
wheelwizardrefurbs
Technical help Q & A
24
24-09-2015 08:35 PM
RSmark84
General Car Related Discussion.
19
13-09-2015 01:29 PM
bigryrs
Ford RS Turbo Parts for Sale
2
07-09-2015 06:45 PM



Quick Reply: EFI Fuel pressure too high?



All times are GMT. The time now is 08:37 AM.