Engine is missing?!?
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Well, the car is missing on the #4 cylinder. I changed the plug wires and plugs. The injectors are brand new 42# Racetronix FM. It is still missing. The opti if fairly new. I am running a MSD digital 6 so I could retard the timing when I spray the car. I am thinking the opti could need a cap and rotor. I dunno. I ran a compression check and the comp. was between 190-200 on each cylinder. So that eliminated a broken ring or and a blown head gasket or unseated valve. What other suggestions does anyone have. Let me know. Wanting to get the car tuned so I finally drive it.
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I have had opti problems before and it missed irratically on all cylinders and this just misses on one. It has about 10,000 miles on it with plenty revs to 6700-6900 which is what my old setup use to turn. It is an OEM piece I have now. I guess if no one has any other suggestions I will just pull the opti off and check out the cap and rotor to see if I have any corrosion. Then order a new one. Just trying to get some insight. It would be an expensive mistake. Someone else please chime in.
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So only the #4 was misfiring before and after the plugs and wires AND the new injectors?
I'm just trying to go down the line.
The only thing that I can think of that are cylinder specific would be: plugs, wires, injectors, or a bad terminal in the cap
A bad coil, icm, or optical sensor would cause random misfires.
I'm just trying to go down the line.
The only thing that I can think of that are cylinder specific would be: plugs, wires, injectors, or a bad terminal in the cap
A bad coil, icm, or optical sensor would cause random misfires.
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I sold my old topend setup and went with AI, so I upgraded to the 42's since I maxed my thirties out. I have read numerous times that MSD boxes cause excessive corrosion in the opti's, that's why I keep on leaning that way. The #4 cylinder is the only one misfiring. It is like it misfires randomly. When I pull the plug it is wet from fuel but, it isn't soaked and the plug is a nice stoich color just a little wet from fuel. I think I have a spare coil and icm. I will try that. I also have a spare opti but, I don't know if it works. I will do some parts swapping I suppose.