Forgedlt4

i just finished up installing a fresh 383 in my 96 camaro. the first time i tried the car started fine. it was late (10pm) so i shut the car off after about 1 mintute of running to repect the neighbors.

the car sat for a day and i started it right up again, and it ran for about 20 seconds and i shut it off due to a neighbor complaining about how loud it was. (open headers)

ALL i did was put exhuast on it and tried to start it up yesterday. all i got was backfiring out the intake. so i checked on here and read it coud be due to valve lash....so i loosened all the valves and re-set them, i got the same backfire and no start. i checked all the spark plugs and they were soaked in gas. i dried them out and re-installed them and then i broke my starter's nose off on one of the backfires.

i searched on here and found that if i didn't have my coolant temp sensor plugged in it would make it run pig rich. i figured that could cause a backfire so i went out and bought a new starter and new coolant temp sensor.

the next day (today) i replaced everything and after 3 seconds of cranking with the brand new starter.... it back fired out the intake and exhuast and the starter broke again.

i didn't dry the plugs out fro yesterday so could this be what caused the backfire enought to break the starter? or is my opti installed wrong or bad.... or something else. i know for sure my timing chain is correct... i check it 3 times)

cehan

The only thing that comes to mind is that it seems ignition related, if you're sure that the valve timing and valve lash is correct. I'd first make sure that the plug wires aren't crossed and then pull the optispark to make sure the cam pin is in the correct slot.

Injuneer

Try resetting the PCM. Running the engine with open headers causes the O2 sensors to get screwed up by seeing the air that mixes with the exhaust at the collectors. That causes the long term fuel corrections to increases and pour unneeded fuel into the engine. Clearing the PCM will reset the long terms to 128 (0%). Might help.

Odd that it ran well at first two starts. That would seem to rule out the Opti being on the wrong pin. Is it possible the timing chain has jumped a few teeth?

arcticz28the383

Make sure none of your plug wires are mixed up. I have started cars with them in the wrong order and they seemed to run fine untill exhaust and intake backfiring started to occur.