strange forklift issue

[NEK5]

Our forklift here at work has been running chitty on and off all night. We found the problem though, well, part of it.

When he pulled the seat cover/hood up we saw the spark plug wire was off on one of the plugs. Put it back on, dropped the hood, started going, then hear a popping noise, like popping a big bubble. Popped the hood, wires off again. Stuck it on, left the hood up and turned the motor on. Got the motor revving up high, and POP, wire pops off again. Seems like anytime there's a decent load on the motor, it pops.

This is a first for me, what the fock would cause this?

Newer toyota lift, BTW, maybe early 2000's model.

 

[4X4HIGH]

Too much resistance can make a plug wire pop off.

Check plug gap, check OHM resistance on the wire(s) and also check cap and rotor.

This is why GM installed a plug wire retainer on the early HEI distributor caps.

 

[wasted wages]

Too much resistance can make a plug wire pop off.

Really ??? how strange,,,I have never heard of this,,,makes sense though..

high voltage hits a high enough resistance to create a dead short and the plug wire pops... ??