No spark, pulsing power on a 86 L body TII swap.

[turbovanman²]

Did a TII swap, did the wiring mods using a 87 Shelby Z computer but I have no spark and fuel. If I check power at the coil, it comes on normaly when turning the key but when I crank, it goes away, same for power at Inj. If I leave the key on, the PM whines and the power pulses. I tried another PM but same. I've triple checked grounds, the wiring mods and all good to go. The guy swears it ran before I did the swap.

So I either have a bum LM or ??????

[BoostedNihilist]

I posted this reply once already, didn't show up so here goes number 2.

2 ignition wires, one IGN2 (no +12 when crank) and one IGN1 (has +12 when crank) Could be the key cylinder went at the same time you happened to be working on the swap... Nonetheless to test this just check the dk. blue wire @ the ign harness for +12vdc at crank. If this is present I would then check the fuel pump/coil relay.. I would probably bypass any switches/relays to see if my LM-PM combo is working... then work backwards to find the problem

[turbovanman²]

Interesting, I'll check that later.

The asd relay is in the PM I believe.

[RoadWarrior222]

If this is present I would then check the fuel pump/coil relay..

Yeah, I was thinking dirty contacts and maybe arcing at either fuel pump or ignition relay.

Also wondering if the coil is getting hot/warm. Sometimes before they test dead they'll tend to get hot quick, suck too much power. Sometimes this means you can start the car if you go straight from off to starting position without pausing in run.

Then sometimes, machines, electronics and electrics just like to play games, if you fix them or put them together while being doubtful about something, they won't work. Even if you did actually get everything correct. When you double check and KNOW everything is correct, they will then work. So if you've got a nagging doubt about something, prove it wrong. Then having determined the state of that particular cat of the Shroedinger variety, your function as sentient observer is fulfilled and it will now work.

[turbovanman²]

Yeah, I was thinking dirty contacts and maybe arcing at either fuel pump or ignition relay.

Also wondering if the coil is getting hot/warm. Sometimes before they test dead they'll tend to get hot quick, suck too much power. Sometimes this means you can start the car if you go straight from off to starting position without pausing in run.

Then sometimes, machines, electronics and electrics just like to play games, if you fix them or put them together while being doubtful about something, they won't work. Even if you did actually get everything correct. When you double check and KNOW everything is correct, they will then work. So if you've got a nagging doubt about something, prove it wrong. Then having determined the state of that particular cat of the Shroedinger variety, your function as sentient observer is fulfilled and it will now work.

Coil is fairly cool. Tried another known good PM with the relay, same problem. Will go over it again tonight.

[BoostedNihilist]

The whining is characteristic of a faulty relay coil... or faulty source to the coil... I would DEFINITELY check your IGN1 line into your PM.. especially if BOTH PM's are doing it, it is semi definitely not a problem with the pm (what are the chances of two bad ones right?)

A soloution... take a SPDT relay and piss on the ASD inside the PM. that is to say make the ASD relay external to the PM... bit of a hokey work around but should work...

[turbovanman²]

Ok, someone slap me. The pulsing power and whiny PM were due to me having the injector harness plug undone. I was checking powers and grounds and had no grounds at the LM but one set had power?????? I traced around and forget I had undone it to check. While tracing the wiring again, I found the dist connector under the air filter box had come loose-I believe that was the problem but can't be sure. I hooked everything back up and she runs like a champ. Now to fix the low fuel pressure,