We have gotten the 350 into the car (Former MPFI 2.8 V6), and everything attached. We hooked up what little wiring we needed that was in the car to the 350 (dizzy, alternator ect.) We have "made" a hook up for the temp gauge and adapted the 2.8 oil pressure sending unit to the engine. We have not cut any wires at all. When the engine was finished, it ran like a mother on the test stand, but it has only ran for 30 seconds one time since its been in the car. The lead tech at the dealership said all of the unhooked senors still leading into the ECM are confusing the computer and keeping the car from running. He also said that we would basically have to rewire the car and gauges. Does anyone know when the last year was for a fully carbed firebird? We were thinking we could use the harness in place of a full rewire. Any help would be greatly appreciated. Thanks (I know that was a long read)

Wait, aren't you putting a carbed 350 in this car?

So, what is it lacking - fuel, compression, spark?

Other than lengthening and reterminating some wires,

1987.

All you need is the stuff that goes to the firewall bulkhead connector in the back driver side corner of the engine compartment. From your V6 harness, you need the ignition power wire (went to the coil), tach wire (if so equipped - also went to the coil), oil pressure gauge sender, temp gauge sender, alternator wires (will probably need to lengthen). You could get that harness from any V8 car, but one that has the alternator in the same place as your engine would make it easier. '82-'87 V8 carb'd would be the best choice, most likely.

You may need to rewire the fuel pump relay if you remove the ECM.

Something tells me you have a mechanical fuel pump on the engine, and the in-tank electric isn't running (and you didn't do anything to accommodate the in-tank electric).

Wrenchp - We have a carbed 350 on the car

five7kid- Forgot to mention we have an inline fuel pump with regulator...old in tank pump has been removed and the pickup has been extended down. It is also hooked up and pumping plenty of fuel. We are getting fuel, compression and spark. Im going to talk to my dad and see if we cant try to look over the wiring again. Thanks

if u ahve a carbed 350 in the car. The old ecm shouldnt even be in the car. and if it was you have nothing to hook it to. meaning the ecm isnt causing any problems, unless you have a really bad wiring mess.

We looked at it again and it appeared to be the hot wire for the HEI. We were getting spark sometimes, but not all the time. We rewired the dizzy and we were able to drive it for the first time sunday, and it doesn't have any brakes. (First time car has moved under it's own power in over a year, previous owner thought it would be fun to go mudding)