[DMCForum] CPR education for McCoy (Was: Problems starting)

["cruznmd" <racuti1@xxxxxxxxxxxx>]

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)

Yahoo! Groups Sponsor

ADVERTISEMENT

---

Yahoo! Groups Links

• To visit your group on the web, go to:
  http://groups.yahoo.com/group/DMCForum/
   
• To unsubscribe from this group, send an email to:
  DMCForum-unsubscribe@xxxxxxxxxxxxxxx
   
• Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.