testing for spark outside engine + more

[SubaruNation]

hi guys, so this is the deal:

so my soob is living on 3 cylinders... all but cyl 4 specifically.

i pulled the plugs to verify sparkage and to test compression. The cylinders tested with good results, all compression above 135 and the spark plugs visually showed that they were working bc they are black and show use.

SO.. i pull number 4 and test compression and notice a couple of things.. 1. the spark plug shows no sign of use.. it's seriously like scrubbing bubbles attacked it or something.it's CLEAN...?. 2. there's a wee bit of liquid on it and it smelled like fuel. im almost positive the coil was in and on the spark plug as it's real hard to verify with how hard it is to get them back in.

then after the above i test compression and it flats at 120.. but it does go up to 150 on the first 2 cranks.

so after learning all the above i believe there could be a couple of things wrong.

1. the coilpack (these are coil-on-plug for teh DOHC) is not pushing spark
2. the wires are messed somewhere

so i would like to test for spark outside the car..

On cylinder 2, that i know is working bc of the plug i pulled from it..I have tried touching the threads (on the spark plug) that go into the block on to various things in the engine bay to ground and attempt to get spark outside while cranking the car.. with no results

i did the above as a check to make sure it's not the plug, bc i have tried a couple and also in hope of verifying that my coil #4 is shot.

basically i need help getting my coils, with sparkplug inside them.. to spark outside teh engine so i can verify the coil #4 is shot.. or something else.

thanks for your help,

confusing maybe but i can clarify also

[evolutionmovement]

Holding the plug to the block should show a spark. Do it in the dark, if necessary, but it should be pretty obvious. You can also swap plug wires and see if the problem cylinder moves.

[fishbone79]

Wrap a decent gauge copper wire around the base of the plug and solidly ground it to something on the block. Somewhere I have a "spark tester" that does basically the same thing, looks kinda like this:


I also have one that consists of a bakalite ring with adjustable 'points' that you connect to the plug wire to see how much spark you can get... but this is more for older distributor systems.

Some test lights are made to withstand the juice from a plug as well.

[Legacy777]

They make spark testers that all you have to do is hold it up against the plug wire. Saw this at Advance Auto I believe the other week.

Something like that should work.

[SubaruNation]

so the guy at napa said that checking on the outside of the engine like this is a great way to blow your plugs and cause thermonuclear war so...yeah. i dont want to ruin anything. im screwed enough as it is with this thing sitting in teh garage not moving.

i bought a lil' current/voltage tester light deal that i plan on stabbing wires with.... except i dont know which wires to stab.

there are only 3 that come off of the coil so one of them must be the right one.

this will let me know that i have circuit running to the coilpack and that the coil is not sending electricity to the plug which is failing to spark.

if there is no current i will surely cry haha. i am trying to find out what each wire on the clip that connects to the coil is for and which one i should be checking voltage on.

in the meantime i just found 4 working coils for $110 ... which is epic b/c the stealership wanted $112 for one!
so assuming mine is bad i should be golden when they arrive!