Editing Forums/Z31P/z31-repairs-forums engine-mechanical/no sparky

{{ForumImport
|op_user=sprtcrazy17
|op_date=2009-02-27 02:07:11
|post_count=7
|archive_url=/Z31performance_archive/forum/z31-repairs-forums/engine-mechanical/6819-no-sparky.html
}}

'''sprtcrazy17:''' <small>(2009-02-27 02:07:11)</small>

Finished up my turbo swap tonight, enough to turn it over. Turned over awesome no weird sounds just didn't fire. Checked spark right away and nothing coming out of the coil. Checked the plug going into the coil and that measured to be 12V. Any ideas as to why it's not firing?

The coil was working when I pulled the n/a motor. A buddy of mine (junior85z) is gonna bring me another coil to try that and if that doesn't do nothing I'm swaping back to the 84 n/a harness unless any one has any ideas and what to check.

I'm using the 85T harness in the 84 n/a body.

Thanks,

Joe

----
'''Gregmatic:''' <small>(2009-02-27 02:14:29)</small>

power trnasistor FTW! Check to make sure you plugged all your connections back in, ECU test and all that jazz. Then you can tell me I' right when its the PTU

----
'''sprtcrazy17:''' <small>(2009-02-27 02:21:55)</small>

I tried another power transistor I had laying around, the little thing that amplifies the signal right? Near the coil… Didn't do anything.

Yea everything that can be plugged in, is. I was trying to figure out how the power transistor runs into the ecu though. I couldn't figure that out. Man I wish it were that though.

----
'''SnooZn:''' <small>(2009-02-27 08:15:13)</small>

A DOA CAS can cause this issue.

Are there any codes trapped in the ECU?

When my CAS crapped its pants a while back I had the same problem. Everything seemed to check out and in my case there was NOT a code trapped in the ECU, same +12 at the coil etc., however, the CAS slept with the fishes.

Is this an entire engine swap with a different dizzy & CAS of unknown status?

If you're, comfortable with doing it, remove your existing dizzy and spin it by hand with the ignition on. If the CAS is working you'll hear the injectors click and most likely the fuel pump come on and run to maintain pressure.

If that doesn't happen there is no CAS signal getting to the ECU.

Or if you just have a second dizzy available that is already out of another engine just plug it into the CAS connector, turn on the ignition and spin it by hand. Same as above. Then go ahead and pull the existing unit and swap them out.

Just be sure that if you go pulling dizzys for testing that you '''make sure''' to accurately mark rotor relationships first so you aren't off a tooth when you reinstall them.

I've tried to quickly consolidate the info from multiple threads concerning the harness swap over etc into my head but don't promise to be awake enough at the moment for it to all be sinking it. So some of this may have already been covered by someone else. I also reserve the right to currently be missing pieces of the puzzle.

Long story short, assuming that all other harness related issues are worked out, a lack of CAS signal will result in no injector pulse and no signal for the PTU to switch the coil primary circuit on and off.

PT

----
'''sprtcrazy17:''' <small>(2009-02-27 15:04:04)</small>

He said the engine was running when pulled, then again he said he drained the oil, what a nice surprise.

I'm going to go ahead and swap harnesses today, there's too many wires going to nowhere right now.

Thanks for the tip SnooZn, I do have an extra dizzy from the n/a motor, I'll try it out.

----
'''sprtcrazy17:''' <small>(2009-02-27 18:14:11)</small>

put the 84 n/a harenss back in, no fire. found a coil, swapped, runs. i love spoolage =D

----
'''SnooZn:''' <small>(2009-02-28 01:41:04)</small>

{{Quote|user=|}}

Good deal man. [archived image: smile.png]

I know I've said it before, but will say again, it never hurts to have spares of the small, "mission critical" ignition components tucked away somewhere in the car.

I carry a spare coil, ptu, CAS and AFM under the storage compartment behind the seat. Well… NOW I have a CAS in there. It was the one component that I didn't have a spare for when I needed one.

Luckily, I was only a few miles from home. I could have just as easily been hundreds of miles away.

With 20+ year old components you just never know when one might take a proverbial poop.

PT