Engine miss

[aaron1]

When engine is cold it has a slight engine miss. However after vette is driven for an hour the miss i more noticeable as the engine is now jumping around.

I believe this to be an ignition problem. would a primary ignition issue be the cause? It has new wires and ac delco plugs and new cap and rotor.

I will check the plugs and wires.

Thanks for everyones help.

aaron1

 

[LT4man]

Inspect the spark plugs and ignition wires very carefully.

A crack in the porcelain of the spark plug can do exactly what your engine is doing. The spark plug can be cracked just by tightening.

Ask me how I know!

The ignition wires are easy to cross. Two wires crossed would make your engine miss and vibrate.

 

[aaron1]

I had engine running and the garage lights off and saw that 6 of the plugs were arcing across the porcelain from the boots to the metal on the plugs. The napa wires were also arcing at the rear of engine block.

So I replaced plugs and new wires and it was smoother at idle, however after driving it again for about an hour the miss was back.

A friend of a friend said it sounded like the coil was bad. So I am waiting on a new ac delco coil. He explained how coils behave during temperature change when they go bad.

Thanks for your help!


aaron1