Sources of consistant engine misfire

My 92 carb'ed B2200 has a miss at idle and at cruise, so I had a Mazda mechanic look at it (not a dealer, my step-dad who is/was with Mazdas and More). Even after replacing all the wires and wear items, it continues.

A piece of advice I got was to look for shorts or breaks in the high tension wires by looking, while dark at them after spraying them with saline water. I did so and noticed sparks along all the wires and amongst the cap ends. It was a lighting show of small sparks.

I regret adding salt to the water since it is an electrolyte and probably reveals non-existent problems, and corrodes metal like all hell, but it sure sounds bad. I checked engine ground to see if there is a bad connection, but it seems alright, very little resistance along the wire and no corrosion. A good solid connection at the block and battery, so I don't know wire the sparks would be so eager to jump backward.

if your getting spark off the wires then you need new wires

Yeah, since the wires are brand new, high quality Bosch wires, that's why it's so confusing. It's like the wires were crawling with sparks, after I sprayed them. Anyone else have any experience with this test or with a persistent misfire?

I am having the same problem. I have put 2 new sets of plug wires on and a cap and rotor but the spark is still jumping out of the wires just as you have described. I'll let you know if find my problem. If you find yours please post it up.

how long ago did you buy the wires? maybe they've been on the shelve to long and have dry rotted??? just asking????

Kojac said he bought Bosch high quality wires and the problem was still there. I bought a set from Oreilly auto parts and as soon as I started the truck (in the parking lot) nothing changed sparks still jumping from the wires. So I took those back and bought a different brand from advance auto parts. Problem still there. Last night I tried adding a ground from the engine to the battery. Nothing changed. Gonna check timing when I get off work today.

Forgot to mention both sets of wires appeared to look perfect sealed in original package

same prob here. Thought i just had crap gas/stock carb issue. But popped the hood at night an def see a lil spark show goin on near the plug wires
Any body figure this issue out yet?

Do a compression test.

I think you have a burned valve.