To start, i have an auxiliary fuse box and all fuses are good. If i spray carb cleaner in the engine it will run. But I'm not sure if this is spark coming from the computer or if it's somehow just working like an old one wire pickup truck.
No, unfortunatley I dont have the FSM book. Or a noid light, not sure where to get one. I dont yet have the ALDL hooked up yet or the check light. Without ever firing it up would it give me any trouble codes?
The cool thing is I have two harnesses. One on the vehicle and the other spread out on my work table. I've been going over this thing like a mad scientist. I'm to the point now where I may just get a painless system.
The vat module comes with 2 wires for different hz frequency, green wire 30hz and the newer 50hz blue wire. not sure which one mine is, I tried them both but still got nothing. It states in the instructions "30 hz VATS signal used on some 86-93 PCMs"
Another thing worth mentioning, my harness is from an 87 camaro that did not have VAT. So the plug location B6 did not have the wire for the VAT signal, it was an empty slot. To remedy this, I took a Pin out of the spare harness plug and added it to the good harness.
Well, i'm going to go look for grounds
The ECM, if operating would still collect and store trouble codes. This was the first system with a memory that could do this.
The alcl might need to be in place since its an active port to the ECM.
One thing to always keep in mind on these harnesses....EVERYTHING operates on GROUND path completion, and power is always present. the grounds are used to turn on/off everything. Grounds are used to fire the inj as well. Power is everywhere...its almost like a positive-ground system but not, if that makes any sense...
There are 2 types of ground, grounds that are commons, to frame/earth, OR control grounds that operate everything.
Next would be the low voltage control or reference signals to some things...like MAF, a/c controls, ECM. 5 volts is the common reference from the ECM.
Look for 5 ground wires (blk) that will be coming out of the harness near the oil pressure wire. This G-104 bundle contains the ECM/INJ grounds that usually bolt to the block or bellhousing. I am almost positive the camero harness will be like the Vette harness because of the TPI requirements. It
Might have less grounds being a steel body car, but the TPI on a camero still has the same engine mngt as the Corvette.
Without seeing what you;ve got, I can't guess at what the VATS status really is...2 wires? The Vats system has 15 variables for resistance....That key pellet has that many possible values. It completes a circuit in the switch, but if this was not a VATS harness and/or is a VATS ECM or prom...I dunno..
VATS is suspect because it cuts out the starter and the injectors. Starter bypass are common, so again...I dunno.
The fuse box is of concern....the stock box has certain things paired with others, and its not as simple as it would seem. If the aux box was wires the same way as the original, then its probably ok. There ARE other pathways that can interrupt the inj pulses other than the inj fuses. Csty fuse can cause VATS mishaps...
Use those links and drawings that Oz sent....he's the local genius and
very good at diagnosing these cars. Maybe junkman will jump in.....but he's gonna tell you to fix the grounds before anything else!...and he's right.
The local parts store should have a GM noid lite. they're cheap...under $10 and very helpful to SEE when/if injectors are pulsing.
