RE: Peugeot geniuses Help A StarQuester.

John Goodyear (jjg@optsys.com)
Thu, 27 Aug 1998 13:05:25 -0400

Francios,
Boost Pressure or fuel pressure?
Usually boost pressure is climbing as you are accelerating. I said before
that I walk a fine line with my AFS mods and fuel cut. I have been noticing
this cut more often especially on a hot day with low atmospheric pressure.
It usually happens as soon as the boost builds after I slam the throttle.
With The MBC/VBC on my car boost will spike slightly and settle in at 14.5.
I usually notice it at the spike. Lately, as a learned reflex, when I hit
the throttle my eyes go to the VDO boost gauge and as soon as I approach
15psi I back out alittle. I never really had a problem in the winter.

As Far as The Fuel pressure goes I am 75% sure it is relatively static
without the BCFPR (no Fuel pressure Gauge). I know I'm setting a bad
example but I don't have all my "Pieces In Place" yet.

I think this might all be moot. I personally disagree with Scott Unless
there is a change in the way the injectors are driven. Unfortunately the
only way I know to tell, is with a portable oscilloscope which I don't have.

Chew on it a little while, while we argue it out amongst ourselves. Ask
any other questions you like. I'll let you guys know what the outcome is,
if it is final. And I will prompt again if I need to call on the "Big
Guns".

John

-----Original Message-----
From: Francois Dion [mailto:francois@hyperreal.org]
Sent: Thursday, August 27, 1998 11:35 AM
To: John Goodyear
Cc: turbo@vectorbd.com
Subject: Re: Peugeot geniuses Help A StarQuester.

John Goodyear wrote:

> drives the injectors harder therefore they would fail sooner. The only
way
> I could see it be an injector failure is if:
> The ECU conversions or 87-89 upgrade not only changed the fuel curve, but,
> the way the injectors were fired. If I understood Scott correct, The 87
> uses a 50/50 on/off pulse, with increasing frequency to drive them Harder.
> Could the 88-89 change now drive them by increasing Pulse width duration?

Thing is, you got to have a pulse width that falls within a certain window
of
time.
How much wider can go you?

Without hard numbers, it's pretty hard to say if the injectors are
overdriven
in speed of operation or if the ecu cuts off. Is the pressure going up or
down
at that precise moment? If it's stable or slightly up, the injectors are not
able to deliver at that frequency, if it drops, it's the ecu. Check that on
both model.

Ciao,
Francois Dion (francois@hyperreal.org)

--
Member: FLU #1722, PCNA
http://www.fortunecity.com/silverstone/zagato/101/launch.html
Alfa Romeo, Fiat, Lancia, Peugeot, Volvo, Solex