Help Please

[michael perry]

I have picked up a misfire on the back right piston of my engine , I have replaced the plugs, spark plug cables, points and had the timing checked, but it is still there do I need to replace the the distributor cap and rotor arm, any suggestions would be most welcome

[Henry Rifle]

If it's one cylinder only, I would start with a compression check.

[michael perry]

ok thank you for that

[rspears]

Since you mentioned points it's an older distributor, and likely an older coil, too. You might get lucky and find a carbon track or even a crack that has become a carbon track between that one pin in the distributor and the center, or to ground? Pull the cap and check inside with a bright light. While you're looking, check the condition of the eight electrodes around the inside, and the brass conductor on the end of the rotor. Jack's probably on target with the compression check, but I'd look at the distributor cap just in case....

[jerry clayton]

Back right cylinder???? how are your plug wires routed and have you put headers on the car??????????

Looking for burnt/ shorted plug wire to exhaust manifold-------

[34_40]

He says he's replaced the plug wires in the original post.

To the OP, Have you looked inside the distributor cap for arcing / shorting on that particular connection?

[techinspector1]

Could be a cam lobe going flat. Remove the valve cover and observe all rockers for moving the same distance up and down.

[HOSS429]

by misfire do you mean it hits now and then or not at all ?