Alvon,
If it wouldn't crank, how did you check for spark?

 

If it wouldn't crank, how did you check for spark?

Wrong choice of words, . . . sorry. The starter and engine spin normally when trying to crank, but the engine doesn't run or even give a hint of wanting to run. There appears to be no spark (or so very weak that it isn't visible in a lighted garage)from the spark plugs.

 

when you turn the key to the on position do you hear the fuel pump run for a few seconds?

 

If you started the car with the distributor hooked up and the plug wires out, then the spark generated by the coil had to go somewhere. It probably shorted through the coil.

The tegger.com site (the link is in one of the stickies at the top of the page) talks about this and has some pics of a shorted coil. If you test the compression again, disconnect the electrical connector(s) to the distributor and coil.

 

i can't see damage to the coil from doing a compression test with it still hooked up. after all, those specs are assuming the coil is 68F, any hotter or colder will raise/lower the resistance. if the coil is about 68F and the reading is still 11.3kOhm replace it to start with.

first be sure to check that the distributor connectors are not loose, and are tight and secure. make sure the ignitor push contacts are tight and secure, this is important.

(omg michelle mccool = hotness)

like stated - do you hear the fuel pump running? it's possible your main relay took a crap coincidentally. i'd go back and double check everything you touched when you did the compression test.

make sure dizzy has ignition voltage -the black/yellow wire has battery voltage with the key on, engine off in the dizzy connector. this is important because although the ignition switch powers the car, there are 3 junctions on the way to the dizzy(under dash fuse box and two connectors)

(batista is a monster...heh)

 

I see this all the time. If you dont disable the ignition system during a compression test you risk burning up your coil.

And I wanted to add one thing just to help save someone some time down the road: If the resistance test of a coil is out of spec, the coil is bad.

If the restance check of a coil is within spec, that doesnt mean the coil is good. Seen a lot of techs get fooled by that over the years.

 

when resistance checked out good i've only had them fail hot or fail under load. but never had them fail during a compression test. maybe i've been lucky!

 

Hahaha, i've watched techs do it for years before one craps on em, especially the young guys.

See these posts on the internet all the time: I just did a compression test and now my car wont start, HELP!!! Did you disable the ignition during the test? No.

 

yeah, that's me, the younger guy, heh. thanks for the tip.

 

Well, it happens to us older guys, too. We are too stubborn to learn new tricks at times.

Anywho, here's the verdict: Replaced the coil, and everything is fine now. Apparently I overstressed it by running the compression test without disabling the coil.

Thank you all for your inputs!!

Alvon