[NateB68]

'68 cougar with a 302. it misses beats ONLY at idle almost like hiccups constantly every 2 seconds, but isn't misfiring, you can here a mild constant pop noise from the exhaust only at idle. it has new plugs and wires, distrib cap, timing is set dead on 6 degrees. doesn't burn any oil, never has stalled. it only does this at idle. throttle response is fine. it does this both warm and cold. please help its really starting to aggravate me.

much appreciated, Nate B

 

[Bad69cat]

I'd double check the plug wires including coil, then start checking for a vac leaks - I bet you find one.

 

[towcat]

Could be the beginning of a burnt exhaust valve, hope I am wrong!

 

[wbferran]

'68 cougar with a 302. it misses beats ONLY at idle almost like hiccups constantly every 2 seconds, but isn't misfiring, you can here a mild constant pop noise from the exhaust only at idle. it has new plugs and wires, distrib cap, timing is set dead on 6 degrees. doesn't burn any oil, never has stalled. it only does this at idle. throttle response is fine. it does this both warm and cold. please help its really starting to aggravate me.

much appreciated, Nate B

nate, i have been chasing a miss at idle on my 70 351W for a long time. i was out of ideas so i paid the money for a dyno diagnostic. short story was it was in pretty good shape. long story was a different combo of needles, jets, distributor would help (lots of money for the dyno tune!), but probably not improve overall drive-ability much. very annoying i know. if you find anything interesting please let me know-

billy