I'm trying to solve a high idle problem on my 1985 GL before an emissions
test in
late January and I would appreciate any help.  When cold the idle is a
little high
about 1000 RPM. It never really idles any lower than 1000 RPM.  If it the
idle was no
higher than this I think I would be satisfied.  As the van warms up the
idle will increase
to 1200 or 1400 rpm at idle for a few seconds then decrease again.  When I
come to a
stop the engine returns to idle slowly halting around 1800 rpm for a few
seconds then
around 1400 for a few seconds then finally settling down to 1000 RPM.  When
the van is
fully warmed up the idle will sometimes be very high, 1800 rpm, for a few
minutes .  This
happens especially when I stop the van after it has fully warmed up and
restart it in 10
minutes.

So far I have replaced/tested the following over the past few months.
- plugs, wires, distributor cap and rotor
- replaced small vacuum hoses to vacuum advance, fuel pressure regulator
- measured manifold vacuum (around 10 - 12 psi )
- replaced O2 sensor
- replaced temp II sensor

Replacing the above items has made the engine run much better but the idle
problem
has not really changed.

Here are the results of my test.  Switch on ignition to pressurized fuel
system.  Initially it
was 38 psi and after about 10 minutes the pressure was 34 psi. This seems
to be in spec.
At idle the fuel pressure was 34 psi. This seems to be high as the manual
says 29 psi.

I'm planning to replace the fuel pressure regulator. Does this seem like a
good step?  High
fuel pressure would seem to match most of my symptoms (all except the high
idle when
restarting hot).

Is it hard to replace the fuel line items?  Can I use regular hose clamps
or are there special
clamps required?  Any risk of cracking or breaking the 18 year old fuel lines?

Thanks in advance,
Ron Maxseiner
1985 GL 'Stinky Pete'