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Need some help with a cis 8v
--Bosch Fuel Injection & Engine Management, By Charles Probst, SAE...
Continuous Injection-Theory, pg 11
" In continuous systemes control of fuel pressure is extrememly important,
even more so than in pusled systems. As you'll see, fuel pressure opens the
fuel injectors, and the control systems manipulate fuel pressure to alter the
basic air-fuel mixture when compensating for differeent operating
conditions. It's vital that the fuel system not only supply adequate fuel for
the amount of air the engine is using, but also that the fuel be under
pressure, maintained and controlled within a narrow range.
" The fuel system includes the fuel tanks to store the fuel, the electric
pump to pressurize the fuel, athe fuel accumulator to damp pressure sugres in
the system, the filter, the fuel distributor to meter and distribute the fuel,
the pressure regulator to maintain primary system pressure, and the injectors
to atomize the fuel..."
Allyn,
I quote this so that perhaps I can skip some of the dialogue back and forth
and we both get to the meat of this topic... What you are calling the fuel
pressure regulator is in fact the accumulator. It is right next to the pump.
Its' job is to "damp fuel-pressure surges and to hold residual pressure in the
system when the engine is shut off." The "System-pressure regulator" is the
item that hangs off the fuel distributor... On the low-compression engines,
it is bolted to the distributor (which is black in color) by means of a clamp,
and it has a distinct fuel line to and from it, with a two-connection plug
connected to it. On the high-comp. engines, is is bolted directly to the fuel
distributor (which in this case is machined aluminum), has no lines to it, and
has IIRC a two-connection plug also... Pg. 13, "The system-pressure regulator
maintains system pressure (sometimes called preimary pressure) in the fuel
system at the specified level." It goes on to explain the two types, which I
have already done...
Hopefully this clears up some of the confusion about these two items and their
function...
Cheers,
David
Quoting Allyn <amalventano@sc.rr.com>:
> cis _does_ have a fpr, a 5 bar one, its mounted up front next to the fuel
> distributor.
> something has to regulate pressure at 75 psi, ya know...
> Al
>
> ----- Original Message -----
> From: "David Utley" <mr.utility@highstream.net>
> To: "Calimus" <calimus@techography.net>
> Cc: "Allyn" <amalventano@sc.rr.com>; "Scirocco-l" <scirocco-l@scirocco.org>
> Sent: Monday, April 12, 2004 6:01 PM
> Subject: Re: Need some help with a cis 8v
>
>
> > Digifant would have a fuel rail, but CIS will not. Also, not to split
> > hairs
> > here, but CIS does not have a FPR per-se, they do have an accumulator,
> > that
> > will not be your problem unless it is near completely clogged with
> > something... I think your trouble is either a grounding problem, or the
> > ECU... I think it unlikely to be your fuel dist., unless one cylinder is
> > not
> > firing at all until, but that should be all the time, and not have
> > anything to
> > do with the fuel dist....
> >
> > William, if you get that book I mentioned, you will figure it out, I
> > guarantee
> > you...
> >
> > David Utley
> >
> > Quoting Calimus <calimus@techography.net>:
> >
> >> Hrm, I realized that I left something out. The engine I'm refering to
> >> is/was a cis engine as well. Basicly I transplanted the 8v from the
> >> wifes old 89' cabby to the new 89' cabby.
> >>
> >> The fpr pretty much is my next stop. If it still acts up then, only
> >> things left I can think of are ecu, icm and the fuel pump.
> >>
> >> William
> >>
> >> Allyn wrote:
> >>
> >> > i would check the fuel pressure at the rail, or swap out the fpr. it
> >> > may not like the high volume from a cis pump (if you've still got one
> >> > in there).
> >> > Al
> >> >
> >> > ----- Original Message ----- From: "Calimus" <calimus@techography.net>
> >> > To: "Scirocco-l" <scirocco-l@scirocco.org>
> >> > Sent: Monday, April 12, 2004 3:29 PM
> >> > Subject: Need some help with a cis 8v
> >> >
> >> >
> >> >> Ok, basic description of the problem is that the engine appears to
> >> >> have a miss at idle that stays noticable through the rpm range. Also
> >> >> have to have the fuel mix very rich in order to keep it idling.
> >> >> Engine also will not idle when first start, you must keep it around
> >> >> 2k rpm untill the engine warms up a bit.
> >> >>
> >> >> Now, here are the things I've checked or replaced.
> >> >>
> >> >> plugs (replaced)
> >> >> plug wires (replaced)
> >> >> dizzy cap and rotor (replaced)
> >> >> injectors (replaced with used but from known running car)
> >> >> Timing is dead on balls (cam/crank)
> >> >> Compression check is good (160, 155, 162, 153)
> >> >> Getting spark to all plugs
> >> >>
> >> >> I think that covers it. This engine was recently swapped in, using
> >> >> the current fuel setup. It ran fine in the car it came out of. The
> >> >> previous engine had the warm up issue as well, but not this missing
> >> >> BS. Any ideas are welcome. I may have forgotten to list some of the
> >> >> things I did/checked but thats about the jist of it. My current
> >> >> thought is that it might be something with the fuel distributor but I
> >> >> thought I'd check with the list before I swap that out. This is on
> >> >> my wifes 89' cabby BTW
> >> >>
> >> >> William S.
> >> >>
> >> >> --
> >> >> 88' Scirocco 16v (Crabby 16v)
> >> >> 89' Cabriolet 8v (Silver bunneh) 71' Karmann Ghia (air sucker)
> >> >>
> >> >> http://www.techography.com/scirocco (s.org forums)
> >> >>
> >> >>
> >> >>
> >> >> _______________________________________________
> >> >> Scirocco-l mailing list
> >> >> Scirocco-l@scirocco.org
> >> >> http://neubayern.net/mailman/listinfo/scirocco-l
> >> >
> >> >
> >> >
> >> >
> >> >
> >>
> >>
> >> --
> >> 88' Scirocco 16v (Crabby 16v)
> >> 89' Cabriolet 8v (Silver bunneh)
> >> 71' Karmann Ghia (air sucker)
> >>
> >> http://www.techography.com/scirocco (s.org forums)
> >>
> >>
> >>
> >> _______________________________________________
> >> Scirocco-l mailing list
> >> Scirocco-l@scirocco.org
> >> http://neubayern.net/mailman/listinfo/scirocco-l
> >>
> >
> >
> >
> > David Utley
> > -----------
> > Cable Volkswagen
> > 405-470-3129
> > 1-800-522-6793
>
>
David Utley
-----------
Cable Volkswagen
405-470-3129
1-800-522-6793