Machine gunning on acceleration, loss of spark

[Stewart]

The 73's mad at me after 7 months of not being able to drive it. It started out with an intermittent miss and backfiring in first and second and then would run fine for a decent period of time. However if I got stuck in prolonged traffic sitting still it would return then disappear. Well tonight it came back with a vengeance. Went to dairy queen for a malt and she stalled in the drive through line. Fired right back up but was not running well. Leaving the drive through for the 1/2 mile drive back she was sputtering and backfiring like mad. If I didn't have an electronic ignition I would say a condenser went out.

Got home put the timing light on it and long periods of no spark on 1,2,3 at idle and steady spark on 4. Changed the cap and rotor no change. If I rev the car up I get spark but under load it will machine gun out the tail pipe. Did my Petronics go bad or could I have a bad coil?

 

[JPSmit]

timing?

 

[Stewart]

So far I've changed coil, petronix, cap/rotor ground strap in the distributor no change. I did pull the plug on 1 and the engine did change rpm and it shocked the living daylights out of me just by touching the wire so there is spark. Bad plug wires?

 

[JPSmit]

plug wires an any easy change - likely worth trying

 

[Stewart]

plugs it was the plugs. New set of ngk's and it's back to running great.

 

[mgnewbie]

I am having similar problems. What number NGK plugs are you using? YB

 

[Stewart]

NGK BP6ES

 

[JPSmit]

plugs it was the plugs. New set of ngk's and it's back to running great.

always the simple things

 

[mgnewbie]

Thanks. I'll let you know if the new plugs will solve my problem. YB