[DMCForum] Re: CPR education for McCoy (Was: Problems starting)
From: "cruznmd" <racuti1@xxxxxxxxxxxx>
Date: Wed, 22 Dec 2004 18:58:09 -0000
Ryan,
The CPR can warm up quickly. Usually faster than it takes for the
temp gauge needle to move. Because you have more power for that 1st
minute, and because the noise doesn't happen it's possible that your
CPR pressure is too high after it begins to heat up. The back-
farting you describe on deceleration is caused by a lean fuel
condition.
Just like I told McCoy, you should buy or borrow and Bosch K-
Jetronic fuel pressure test rig. John Hervey lends his out
sometimes. You should call or write him if you can't buy one for
yourself. They are available on JCWhitney.com.
The fuel pressure rig can tell you what your primary line & hot &
cold control pressures are vs. the nominal values listed in the
manual. If you're really desperate, see if a fellow owner will swap
CPR's with you and observe if the car behaves better.
If the pressures are correct but you still have the back-farting,
your injectors may be clogging, and the lesser control pressure may
be allowing enough fuel to shove it's way through your injectors for
that 1st minute. That's what was happening to me. I finally pulled
my injectors for a visual delivery test in a 6 pack of glass bottles
and found that 3 of 6 didn't spray and 3 of 6 sprayed poorly.
I hope this helps,
Rich A.
#5335
--- In DMCForum@xxxxxxxxxxxxxxx, "ryanpwright" <yahoo1@xxxx> wrote:
>
> Hey Rich,
>
> I can't help but wonder if this could be contributing to my "glug
> glug" noise (thread posted on the DML). The problem is the car
does a
> "glug glug glug" on deceleration. Here's the catch: It doesn't do
it
> when the car is first started cold. I get about 60 seconds of
driving
> before it starts happening.
>
> I noticed another issue just the other day as well - The car seems
to
> have much more power when it's cold. Once the glug glug starts,
> acceleration is noticably decreased.
>
> I do NOT have the typical CPR problems. The car starts cold on the
> first try every time and idle doesn't seem rough to me. The engine
> does not cough and sputter on acceleration when cold. In fact it
runs
> almost perfectly when cold, the problem starts once it's warm.
> (actually, I hesitate to say that - the problem starts within a
minute
> or so of starting a really cold engine - long before the engine is
> what I'd consider to be "warm").
>
> Is the CPR a possible culprit here? How do I test the thing?
>
> -Ryan
>
> --- In DMCForum@xxxxxxxxxxxxxxx, "cruznmd" <racuti1@xxxx> wrote:
> >
> > Tom,
> >
> > The "CPR" or control pressure regulator provides a constant
pressure
> > against the metering plunger in the fuel distributor.
> >
> > As you know, the air/flow meter is like a see-saw. When you push
on
> > the pedal, the throttle plates open, vacuum(air flow) sucks the
big
> > disc down and pushes metering plunger up. The CPR provides a
counter-
> > force pushing the plunger down.
> >
> > The big deal with the CPR is that it has a "warm up" cycle.
Inside
> > the thing is a heater element. When the engine is cold, the
diaphram
> > is in a different position, providing less counter-force,
allowing
> > the plunger to move up more easily, giving the cylinders more
fuel.
> > After a couple of minutes the heater in the CPR causes the
diaphram
> > to change, increasing the counter-force against the disc,
cutting
> > the fuel to the proper amount for a warm engine.
> >
> > There's a little more to it than that, but I'm just giving you
the
> > basics.
> >
> > Troubleshooting:
> >
> > If the CPR is clogged or the element is ruined your control
pressure
> > could be higher or lower than it's supposed to be during normal
> > operating conditions causing hard-starting, poor fuel economy,
loss
> > of power, etc.
> >
> > I've no idea of the history of your car so I can't say if the
whole
> > fuel system is shot and needs overhauled or what. Your best
> > investment would be an $80.00 Bosch K-Jetronic fuel pressure
test
> > kit from JC Whitney. Properly used, this can save you hundreds
of
> > dollars in unnecessary parts purchases from guessing.
> >
> > Rich A.
> > #5335
> >
> > --- In DMCForum@xxxxxxxxxxxxxxx, "thomaspaulmccoy"
> > <thomaspaulmccoy@xxxx> wrote:
> > >
> > > Walt I think you might be on to something. I couldn't figure
out
> > > why the CPR would cause my problem. Maybe I need a better
> > education
> > > on what a CPR does. I thought it was a fuel capactor, keeping
> > fuel
> > > pressure constant.
> > >
> > > > You need to better define what you mean by "a while".
> > >
> > > That is technical lingo fo' "I haven't had time to
scientifically
> > > study it". It seems as though trying to restart it anywhere
from
> > 20
> > > minutes to 1.5 hours later is futile. During this period of
time
> > > the only solution is pushing the car then popping it in gear.
> > >
> > >
> > > TM (recluse VIN 6921)
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