intermittant spark

[tom3]

Good day sir, here is the email requested. 

 

                Vehicle arrived at shop by tow truck. 
Vehicle at first would start every time..  ( noticed left rear brake line
leaking and advised customer/left rear tire).. unable to duplicate no start
concern..  after 3^rd or 4^th day finally got the vehicle
not to start. Checked compression( cyl #1 135psi, cyl #2 130psi, cyl3 and 4 at
135psi(slightly low but not low enough to cause a problem)  Checked for fuel,
did have correct fuel pressure), vehicle was getting no spark( to the plugs). 
Spark was coming from the coil to the distributor(nothing from distributor to
plugs).  Checked power and ground to distributor, to make sure when vehicle
cranking over, ecm saw signal..  it did not.  The crank angle sensor on the
distributor was not showing output.  Took timing belt covers off to be sure
everything ok.  No concerns, no slip/break, all within specs.  Tested with known
good distributor at this point.  Vehicle started at that point but ran for about
10 seconds then shut off.  Again, no spark to plugs.  Retested everything as
before, then found no spark coming from ignition coil.   Checked resistance in
the coil to see if ok( primary side had .8 ohms and spec is .8-5 ohms/ checked
secondary side..   had 17.1 kohms.. spec is 8-12kohms).  at this point installed
and tested with a known good coil.  Oem coil went to .9 on primary and secondary
went to 11kohms.   still no spark from coil.  At this point all specs are within
ranges on all systems and no spark from coil.  At this point is where the trail
ended.  

 

Note: the dealer has had the car for over a month, tested it with new distributor, new coil, etc., and still has not got it to keep running.  There is/has been intermittant spark.   I thought it might be a ground or possible bad wire/connection from the ignition module, but they haven't found any so far.  Car went in 9/23... still there, but they said "come get it, we quit":-(

 

 

[1 Lucky Texan]

details on car? year/miles/condition etc.

[tom3]

1991 Subaru Loyale wagon: 220,979 mi. (1428 since new timing belts). VIN JF1AN4220MB417193  Car ran very well before it quit... no oil consumption, excellent acceleration, no misfiring.  It has been well maintained.

[Fairtax4me]

You'll want to post this on the old gen section where the EA engine guys can give you better advice.

Shouldn't be that hard to figure this out. There are only a few components that control spark, but I don't know enough details about that engine to be of much help.

[john in KY]

The coil bracket has to be grounded. Remove/clean/replace and see if that solves the problem.  

[somick]

Yes, post it in the "Older Generation"

 

As far as I know they have different distributors for different years.  So make sure you are testing it with the correct one. 

 

There is a transistor mounted next to the coil.  You may also need to get a known good one and test it.

 

Good luck,

Sam

[DaveT]

Try starting and running while holding the throttle slightly open. If it dies only when you let it go to idle, it may be in the iac circuit. I had one do that.

[Dee2]

sounds very much like a grounding problem.

[crazyhorse001]

Ignitor. You'll get spark once, then not again till key off/on ycle.