Misfire under load?
 

Hey guys, car in question is no hotrod. 1991 honda civic. It is a 5 speed manual and I am experiencing an extreme misfire ONLY under load. For instance if I put it in 4th or 5th and floor it with the vehicle speed around 40mph, the engine will jolt and misfire causing the whole car to bounce around. Also if I select too high a gear and go uphill I will have the same symptoms. I am leaning towards an ignition issue (maybe the plugs just need changing) because I believe a weak spark could cause this. If you guys could give me some possible causes for misfire under load it would be greatly appreciated.

Thanks,
Keith :)

I would start with plugs if one is trying to foul it will do what you are saying. That would be a good start.

I don't know anything about honda specificly.. is that a single ignition coil with a distributor? coil packs? coil-on-plug?

in a car with a single ignition coil, a bad coil will cause the same effect.

more specifically, a coil that is "going" bad. under high loads, it requires a lot more electrical energy to fire the plugs and puts the coil under higher loads and can aggravate a marginal situation.

Ayuh,... Change the fuel filter,...

A Lean condition can cause those symptoms...