Backfire from intake?

[DEN 14]

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[TD="class: odd, bgcolor: #E9E9E9, colspan: 3"]Car was starting before I replaced water pump on 1992 LT-1. I was very careful to not get the Opti wet. Everything is back together now and it won't start. It has spark since it belched a flame from the throttle body. New injectors, FPR, plugs and MAP. It was suffering from a rich condition before the pump was replaced. Plugs were fouled and the carbon deposits were from this condition. Where to start to look for problem now? I have a new OPti sitting here and I can install it but I wanted to troubleshoot the no start problem first. Has anyone ever had a bad Opti cause a back fire such as this. The opinion I have read on the forums is that it just quits. Stored codes are H42 and H64. I found a bad plug wire while changing the plugs and I am waiting on a new set to arrive. I tried to start it with the injector with no wire to the plug disconnected. Not the smartest thing I guess but every V8 I have had will start and run on 7 cylinders. In the starting sequence, the coolant sensor is involved to some degree and it is new so I would like to rule it out as suspicious. Is there a way to ohm it out? Sorry this is so long but I am puzzled...Thanks!
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[WhalePirot]

Backfire.. so you have fuel and ignition... LOL Just one, at least, must be firing at the wrong time. Carefully check the firing order then recheck it. Seems you pulled the plug wires (right?) and it is possible to misconnect them, even with years of working on cars... so I hear... LOL

Are they 180 out?

I'd do the full tune procedure, checking fuel pressure, TPS sensor voltage, timing (ESC disconnected), all per the FSM.

I chuckled at paying for an AFR, then setting the factory number.

 

[DEN 14]

Backfire.. so you have fuel and ignition... LOL Just one, at least, must be firing at the wrong time. Carefully check the firing order then recheck it. Seems you pulled the plug wires (right?) and it is possible to misconnect them, even with years of working on cars... so I hear... LOL

Are they 180 out?

I'd do the full tune procedure, checking fuel pressure, TPS sensor voltage, timing (ESC disconnected), all per the FSM.

I chuckled at paying for an AFR, then setting the factory number.

Haha! Got fuel and fire for sure. Just don't want the rest of the car to be ON FIRE! I will retrace my steps on wires. Is the backfire possibly caused by not having the one cylinder connected? If so I will just wait for the new wires before I even try to restart it. I am very leery of fire even though it was only out of the intake. Hate to kill a car with a bad call.

 

[WhalePirot]

Is the backfire possibly caused by not having the one cylinder connected?

Not in my experience. More likey the timing is 180 out or reversed rotation. Can you not repair the faulty wire? I have has luck by cutting off about 1/2" on the spark plug (most oft pulled) end, then reattaching the terminal and boot.

 

[DEN 14]

Waiting on the new wires to get here. Should be in tomorrow. Going to install the new Opti while I am at it. It will probably be easier to run the new wires with everything exposed anyway. Should be some great practical experience too.