Cranks and Fires, but won't stay running...diagnosis

[drhill]

my 84 Wagon stalled on me the other day, definite burning wire smell from inside the dash. I waited a few minutes and it started up and got me home. It happened again in my driveway this afternoon (along with burning wire smell) but now it won't stay running at all. It will crank and fire, but it won't stay running. I pulled the small red push on connector at the starter solenoid while my wife cranked it and it would stay running as long as she held the key to cranking position.

I checked my 84 and 88 EVTMs (it's a CFI to SEFI swap) and it appears the Red/green wire from the ignition switch to various relays (fuel pump, EEC) and the TFi is the culprit. It's hot in run. There is another wire that's hot in start that bypasses this wire, that is why it would run if we held it to "crank" and manually disengaged the starter.

I don't get 12v with ignition in RUN at either of the relays or at the TFI. I did get some resistance between the TFI and the ignition switch on the red/green wire when I ohm'd it though...my digital voltmeter wasn't showing a "1" for broken circuit.

Problem is, I can't see any burnt wires up under the dash and I can't follow that red/green wire under the dash very far. I would normally just bypass the wire from the ignition switch to under the hood but there is a factory splice somewhere (either S155 or S311) that I can't bypass so I'm afraid to cut this wire. Does anyone know where the factory splice is? I hate to take apart the whole dash trying to find the short or burnt wire when it would save me so much time just bypassing it. But, of course, I need to keep all the factory 12v in run power to everything... Also - my 84 EVTM does not show any fusible links in this wire, and all my under dash wiring is still from 1984. My 1988 EVTM shows a fusible link in the this wire...?


thanks for any help!

[86VickyLX]

Fusible link for the ignition key on power should be on the drivers side fender. It's a red/green stripe wire going into, iirc a blue fusible link. Also check the connectors over in that area. They get corroded sometimes, and also visually inspect the wiring, the insulation likes to crack off of the red wires especially.

[drhill]

Got it, I'll check the wire in that area and look for the fusible link. My 84 EVTM says there isn't one but my 88 EVTM says there is...it's been so long I can't remember where my 84 wiring ends and my 88 wiring begins!

[gadget73]

Check the ignition switch itself if you haven't. They're somewhat prone to roasting.

*edit*

forgot you posted just yesterday about replacing the switch. Is this happening with the new switch or the old one?

[drhill]

someone I had help me clean up the wiring under the hood years ago, stuck a bunch of wiring inside the fender, I was not aware of that, no wonder the fender had so few wires and I was having trouble finding things!! Well - blown fusible link, caused by bad splice I did way back when. I'm better at that stuff now, going to update several other mediocre connections while I'm at it!

[gadget73]

Good deal, glad you found it

[87gtVIC]

Nice that you found the issue. I am not a fan of wiring/electrical problems.

[drhill]

Yes, neither am I. As the years have gone by, more and more people love seeing my wagon, so it keeps me motivated to push through all these little problems to keep her on the road and the dragstrip. I had one guy tell me he was so happy I didn't swap an LS motor into it. I never even thought about that!