Missing/lean under boost

[David Yentema]

Thank you very much for explaining that, I had intentions of knocking up the
system fuel pressure anyway, but I wanted to make sure everything else was
working as it should be before going and modifying things. This car has the
external regulator, so it's a allen key inside the regulator I need to
adjust, at least from what I understand. You think that is something I can
monitor while I'm driving it? I know I can't really measure system pressure
with the car running, but watching control pressure, would I see it drop
off?

and the reason I was saying it was vapour lock is from what I was reading on
SJM's site, saying that when the residual pressure drops off, the gas
vapourizes from the heat. Leaving the hood cracked seems to help that some.

But, I'll take a look at that this weekend, thanks again.

On Wed, Jun 8, 2011 at 9:19 PM, Scruggs Family <gjkzscruggs at verizon.net>wrote:

> Dave, you have two problems.  One is that you have at least one leaking
> injector... it's not vapor lock... when not running a leaking injector
> dribbles fuel into a cylinder and under cranking it takes a few seconds to
> restore normal system pressure so that fuel will then be distributed to all
> cylinders.  Solution is to replace all the injectors.
>
> Two... your 'missing under boost' problem is caused by a too low overall
> system pressure.  The overall CIS system pressure is regulated by a spring
> that is located at the input to the fuel distributor.  Over time the "k"
> value of that spring will/can decrease thereby reducing the overall system
> pressure.  Disconnect the input line and put one washer behind the spring
> and your missing problem will be reduced if not solved.  Even though your
> system pressures may read within spec... this is the problem.  I speak from
> long and hard experience having had exactly the same problem and replaced
> everything in the ignition and fuel system and finally stumbling upon this
> valve.
>
> Regards,
> Gross Scruggs
> Annapolis MD
>
>
>
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-- 
Dave Yentema
Resident Advisor
Poyda C4th, x2959