how do you test for spark?

[Kent McLean]

Clive Young wrote:
> Interesting problem

I'm not sure I'd use the term "interesting".

> 1.    disconnect the input to the solid state out put stage and measure each
> signal coming from the ecu with a scope.... okay a meter if you have one, it
> would be a fast signal but you MAY see a flicker on your meter, if all three
> are the same fair enough, if one is different it might tell you something.

Hmm, that sounds doable.  But I'm afraid my digital Voltmeter won't
be fast enough to get a reading.

> 2.    check all 6 cylinders for spark as there are three signals for the
> output stage and 3 ignition coils one for cyl 1and 6  ( 2 and 4 ) ( 3 and
> 5 ) .make sure you have them all .

Did that.  No spark on #4 (middle coil on "port" side). Weak spark on
its opposite side.  So I swapped in a spare coil.

> 3.    check the ground connection for the power output stage as it is
> suppose to ground to the intake manifold according to the manual ( brown red
> wire ) .

I try that, too.

> If all checks out okay I doubt spark is your problem.
> 
> The next area to check would be fuel pressure testing off the rail ,

I cracked the fuel line to the rail.  It pumped about 1/2 pint
of gas in about 5 seconds of cranking.  Pressure or volume
may still be an issue, but even so, I would expect the car to
start; it may run run poorly or die quickly, but I would expect
it to start.

-- 
Kent McLean
'94 100 S Avant
'89 200 TQ, "Bad Puppy" is no more