Tapping Park Safety wire on TBI conversion

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MtBraun

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As post title indicates, trying to wrap up a TBI conversion wiring. My 78 K18 has purple/purple white going in to the park safety switch. I'm uncertain which of the two gets tapped for ECM connection on the TBI conversion. I assume one is ground and the other is the one to tap?

Thanks in advance.
 

MtBraun

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whoops, I meant K15. Momentary lapse of 10 key accuracy
 

bucket

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Last time I swapped TBI into a truck, I left that wire unhooked. Or grounded. Whichever way the painless instructions said would tell the ecm it was in gear. That truck had an early Lumina column swapped in, so there was no park/nuetral switch to tap into.
 

MtBraun

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ok - if all else fails I'll ground it.
 

RustyPile

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I may be all wet on this one because I've never installed TBI systems into an older vehicle.. If memory serves me correctly -- at 74 years old, you takes your chances-- the purple wires are for starter solenoid activation (starting).. The purple/wht comes from the ignition switch.. The purple wire goes to the starter solenoid.. Park and/or neutral positioning of the safety switch connects the 2 wires together for starting.. Grounding either one will let out copious amounts of smoke... If the ECM needs to receive a signal for the starting process, I'd say connect to the purple (no tracer) wire.. Voltage (ecm signal) on this wire is an indication that it's safe for the starter to engage...
 

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