Re: Hard-starting 1991 100s

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <7F44DB86FC64D21197A50008C75DB04A3255D1@saexch-mb1-stf.sikorsky.com> "Norman, Victor J" writes:

> I have a 1991 100s (non-turbo, NF engine, CIS-E III). It starts fine from
> cold, but if I turn off the ignition after the car has warmed up and then
> immediately try to restart, it will not start. If I wait just a couple of
> minutes it starts with no problem. A little embarrassing if I stall the car
> in the middle of a busy intersection....
> Any suggestions on fixing this problem would be much appreciated.

Speculating ...

System pressure leaking down _fast_ leaving control pressure so high
that it holds the air mass sensor paddle down?

Over a minute or two, control pressure will also leak down, releasing
air mass sensor paddle.

Diagnostic check would be an interesting variant of the standard
residual pressure test:

a) Attach fuel pressure gauge - tap open.

b) Idle engine to temperature.

c) Shut off engine.

d) Jumper fuel pump relay socket to run fuel pump.

e) Close gauge tap to read system pressure.

f) Shut off fuel pump and watch gauge.

A very rapid decay (<10 seconds) would indicate you've found the
problem.


--
Phil Payne