I have a 305 TPI and i changed out the spark plugs, the wires, the Cap and the rotor over ther weekend. Well when we got it all put together and set the timming on the car, it seemed like one of the cylinders wasn't firing, so i checked it this morning to see if it was just a wire wasn't connected right, and all of them where connected. So i come to find out, that the car begins to fire on that one cylinder when it goes over a certain RPM. Do you guys have any idea what this might be? and will this hurt the car in any form or fashion in the near future?

thanks
jon

 

If this didn't start happening until the tune-up, it makes the most sense that something about the tune-up is responsible for the problem.

Check the wires for proper firing order again. Having 3 and 4 switched, for instance, will cause some wierd things to happen.

If you're completely sure that isn't the problem, then you either have a dead plug, a dead wire, or a cap with a dead or shorted terminal.

It's not a good thing for this to be happening. If a cylinder isn't firing properly but the gas is still getting there, you run the risk of washing the oil off the cylinder, and some not-so-good things happening to parts such as the catalytic converter.

 

Check to make sure the wire that is misfiring doesnt cross any other wires. If a cross is inevitable it should be at a 90* angle.

 

Make sure the cap is on straight and hasn't munged the tip of the rotor. Take off the cap and look.

 

Well i just had a chance to check under the hood on my car, and looked at the rotor, and the rotor is inded grinding against the cap, is there anyway to stop this? and is there a cap and rotor that you would recommend buying that won't do this?

 

They'll all work, if installed correctly. They get trashed because the cap isn't on straight.

I usually use either the Standard Ignition "Blue Streak", or Accel. MSD would also be good.