Random Misfire while cruising

[Zed Head]

Have you measured cylinder pressures? If they are correct then valve seals would be the next place to look.  Pretty easy to replace, easier than replacing oil scraper rings on the pistons.

[Mark Maras]

 @jalexquijano I remember a compression test from a while back but I don't remember the results. Could you post them again? 

[jalexquijano]

4 hours ago, Mark Maras said:

 @jalexquijano I remember a compression test from a while back but I don't remember the results. Could you post them again? 

[siteunseen]

Damn! That looks great.

Maybe crimp your wires tighter on both ends, plugs and dizzy cap. Use dielectric grease too on all connections.

 

Edited October 17, 2020 by siteunseen

[Mark Maras]

Those are great compression numbers. Did you ever try removing #s 3 and 4 spark plug wire and switching them to see if the problem moves to another plug along with the wire?

[jalexquijano]

Ill try that again? Is it necessary to take the car for a spin and get stucked in traffic to do these tests? Or can i just do it leaving the car idling at the parking lot until spark plug fouls?

[siteunseen]

You could do it around your neighborhood. No need to go to traffic and get stuck.

I would do what Mark has said a few times and swap the wires. It could be that simple.

[jalexquijano]

55 minutes ago, siteunseen said:

You could do it around your neighborhood. No need to go to traffic and get stuck.

I would do what Mark has said a few times and swap the wires. It could be that simple.

Actual state of plugs without anti foul extender. 6 5 4 3 2 1 order. 4 being the most fouled.

[siteunseen]

You have a bad wire connection in my opinion.

Plug extenders are quick fixes. I used them on my dirt bikes. They are band-aids. 

[jalexquijano]

I dont think so just try different wires and with the anti foul or directly if you pull the wire from that cylinder there is no change in idle at all. 

[siteunseen]

You must change the whole wire. Like changing a known good battery to a suspected bad battery.

Just use the two that are similar length. Take them completely off both sides of connection then see what happens. Wires go bad believe it or not. The ends get loose and won't "snap".

[jalexquijano]

I had a spare set of 6 ngk wires. Could something be wrong in the dizzy?