My 1988 fc3c had a misfire before I replaced the plugs and wire the misfire went away and came back and now its constant.


I'm thinking maybe the coil packs??

 

I think maybe you put the spark plug wires on wrong??

Front coil plug wires will go to BOTTOM plugs..doesn't matter which plug..they fire the same (BUT the coil marks the wires as L1 and L2..meaning Leading ONE/front lower plug and L2..leading TWO/Rear Lower Plug.)

**THIS "may be your problem HERE
\/\/\/\/\/
TRAILING Coil is Specific so you can't place the wires Just anywhere.They MUST go to the Proper plug.
TRAILING ONE (T1 on coil) goes to the TOP UPPER PLUG@FRONT OF ENGINE.
TRAILING TWO (T2 marked on coil) goes to TOP PLUG at the REAR of the Engine.

Check that out.
It's a common mistake so don't feel bad if it turns out to be that.!

 

I checked there on right
thanks

 

What are your exactly referring to when you say "misfire" ? Is it consistent at a certain RPM range? Idle?

 

Mostly at idle sometimes you can feel it when driving under load like when you start to take off from a stop

 

Make sure the TPS is set properly. Drive the car for at least 20 minutes followed by setting the Green/Red wire of the TPS to 1 volt w/key to on and see if that helps things.

 

Satch beat me to it... that's why I asked under what conditions it did it. I was thinking TPS , also make sure the boots on the wires are fully/properly seated, especially on the plugs...

 

found and removed bad clogged pre cats misfire went away and now its back im going to check the tps