'96 Legacy Outback Intermittent No Start

[Rick]

Hey -

I've got a 96' Legacy Outback that about intermittently won't start
(it happens about once per month). It only happnes when the car has
been sitting all day (ie the car is cold). It turns over perfectly
fine, but no pops or sounds of it trying to catch. Typically I walk
away for an hour+ and come back and it fires up fine with NO CEL light
(no light = no codes), and it runs fine for another month.

Nothing consistent weather wise... it's happened for 3 seasons now, so
I've eliminated cold/wetness.

Plugs, Wires, Fuel Filter, Battery (I checked the battery the other
day for giggles, 12V off, 14V charging, PERFECT) and crankshaft sensor
are all new... I also checked the resistance of the ignition coil (per
the Hayes manual) and it meets spec.

So, two questions:
(1 - the usual) Has anyone seen this before? If so, what was problem?

(2) Does anyone know what part of the ignition system is monitored by
the computer? AND more importantly, what ISN'T MONITORED? Does it
monitor the ignition coil? What about the fuel pressure? Since there
are no CEL codes, the problem is obviously in a place where the car
isn't looking... this way I can try to focus my attention.

Thanks,

-R

 

[japie]

Sounds like a faulty crank or camshaft sensor.
I had the same problem with a ´95 Legacy..

 

[Rick]

I replaced the cam/crank position sensor back in late Feb... besides,
those sensors are tied to the computer and when failing cause the CEL
to come on (which is how I diagnosed the sensor the first time).

-R

 

[Gilles Gour]

I replaced the cam/crank position sensor back in late Feb... besides,
those sensors are tied to the computer and when failing cause the CEL
to come on (which is how I diagnosed the sensor the first time).

-R

Only an educated guess, but here goes. I would bet on fuel pressure. Two
reasons: first is it's not ECU monitored ; second is it takes around
five hours and sometimes more for the fuel system pressure to get down
to zero. I know, i have a fuel pressure gauge on my 96 Brighton.
So maybe there is a problem with the fuel pump or with the fuel pump
relay. I would start by testing the fuel pressure when the problem arises.
My two cents.
Gilles

 

[EugeneT]

I've had the same problem with my 97GT. It happens about 2-3 times a
year... the engine just turns over but doesn't catch. I come out,
play with the wires, tubes, pcv valve, battery contacts...come back in
5 mins and everything's ok. I would be on an air bubble in teh fuel
lines or low fuel pressure alltogehter...never figured out what the
problem was..

If you find out, can u email (e-mail address removed)..

THanx

 

[Rick]

Thanks for the replies!

Low fuel pressure eh? Since I have a new fuel filter, should I be
looking into a new fuel pump? Or was there something else inbetween
the pump/engine that I should look into? ...I seem to remember several
places where pressure could be lost, but I don't have my Hayes book so
I could just be okn crack...

Thanks again!

-Rick