Coupe Hesitation - No Power on Accel

timofej.crift at timofej.crift at
Wed Dec 11 17:14:36 EST 2002

I figure I would move back to the CIS troubleshooting topic, but this time on
plain old CIS.  The patient is a 1984 Coupe with the WE engine.  When the
egine is fully warmed up, there is no power on acceleration.

What I've done:

Rebuilt Engine
All things pertaining to a tune-up (filters, cap, plugs, rotor, wire
resistance, etc.)
Clean fuel distributor plunger
Air plate resistance - even and smooth (in spec)
Air plate height - OK
Aux air valve - OK
Cold start valve (not leaking)
Control pressure regulator resistance - 18 ohms (in spec)
Control pressure harness connector - 13V (in spec)
Control pressure cold - 16psi (in spec)
Control pressure warm - 50psi (in spec)
System pressure - 68 psi, but drops and fluctuates between 64-68 when the
engine is "hot" (out of spec by 4psi, enough of a difference to cause

What I haven't done:

Duty cycle test
Fuel injector comparitive measurement

Also, when checking the system pressure (ball valve closed), the hesitation
goes away.  This would lead me to believe I have a control pressure
regulator/fuel starvation problem (consistent with low system pressure or high
control pressure), but everything seems to be in spec. Again,  the problem
only occurs when the motor has been running for about 15 - 20 minutes when it
is really warm.

If it is the system pressure, do I add or remove shims to bring the pressure


Tim Crift


timofej.crift at

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