GM TBI conversion on a 304 CJ-7

**Texasdave** · 03-04-2016

Went to the Junkyard yesterday and pulled what I hope is everything I need to do this conversion. The donor vehicle was 1989 Sierra GMC pickup. The ECM was an 1227747. The BCC is still to be determined. I did not see any where I thought they should be. However on the ECM with all the information it had ASKF. I believe that is the BCC ID. I'll have to check when I get home to confirm the order of the letters. When I did a BIN search those letters did not come up. Anyone know anything about this chip? I will be going through this step by using the information found on this site. The help here has been tremendous especially david w and Eaglemark. I will keep you posted as to my progress from time to time and seek advice. I am putting it on a 304 AMC bored to .30 over. I will check with the fellow that redid it to find the cam he used.

**Texasdave** · 03-07-2016

Okay, basic question. My Jeep did not come with a check engine light so when I'm wiring in the TBI conversion do I need to wire in some sort of light?

**dave w** · 03-07-2016

Yes.

The computer will supply the "Ground" to the check engine light when there is an error. The other wire of the light is connected to the ignition switch ("On").

dave w

**Texasdave** · 03-22-2016

Working on the wiring harness and and I am unsure of which wires I need and which I don't. I have two multi-port plugs in the wiring bundle that connects to the wiring bundle inside the vehicle (1990 Chevy Pick up donor vehicle). DO I cut these out? I think I should but I'm unsure what they connected to inside the cab. I feel like a bomb tech do I cut the pink wire or do I cut the green/black wire. Only good thing, at least I won't blow myself up.

**dave w** · 03-22-2016

Figure out the ECM wiring first, here is a link to the 1227747 wiring schematics: http://www.gearhead-efi.com/Fuel-Inj...Information-42

dave w

**Texasdave** · 03-31-2016

When I removed the wiring harness it had a bulkhead connector, or at least I thought it was. In reality the wires go straight through and are covered by this plastic goop. I heated the goop and it melted allowing me to separate the wires. This makes it easier to work with them. BTW I was careful not to get it so hot that it melted the wire coating.