Ls swap wiring
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Teching In
Joined: Jan 2020
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Ls swap wiring I知 doing a ls swap on a 1992 Buick roadmaster limited ls1 I知 try to see how to I wiring in my stand alone harness and gauges and my fuel relay and fuel my fuel pump if any one can help it will be greatful thanks
Teching In
Joined: Oct 2019
Posts: 44
Likes: 9
From: Phantombullet
Fuel pump, coils and injectors need relays, and you supply those relays with 12v battery power to pin 30, the PCM then works the 85/86 side of the relays to send the juice to them through pin 87 on the relays. Fuel pump relay pin 87 to your fuel pump 12V , and coil and injector pin 87 12V goes to the correct wire on the engine harness.
Most of the rest pretty much plugs onto the engine and then to the PCM. Im probably missing something in this quick run down but thats about the jist of it. The PCM can control 1 or 2 fans also, if you add electric cooling fans you need to install relays somewhere for those also and get the PCM to switch them.
As above lt1swap is your friend, read up on the pinouts and trace them with a multimeter. There is a tach output from the PCM, as well as 2 different speedo outputs in regards to some of the gauges. The speed outputs can be changed/tuned with HP tuners. If the LS1 tach signal is scaled wrong for your existing tach, you can use a dakota digital tach signal box, I used that in my ford to make the tach correct.
Most of the rest pretty much plugs onto the engine and then to the PCM. Im probably missing something in this quick run down but thats about the jist of it. The PCM can control 1 or 2 fans also, if you add electric cooling fans you need to install relays somewhere for those also and get the PCM to switch them.
As above lt1swap is your friend, read up on the pinouts and trace them with a multimeter. There is a tach output from the PCM, as well as 2 different speedo outputs in regards to some of the gauges. The speed outputs can be changed/tuned with HP tuners. If the LS1 tach signal is scaled wrong for your existing tach, you can use a dakota digital tach signal box, I used that in my ford to make the tach correct.
