Ok i have a 55 crown Vic with a 292, 3 on the tree...About 3 weeks ago i installed a pertronix system the car runs great starts right up and seems to run fine...But my idle isnt so great almost like a miss i give it a little gas it clears up...the carb was rebuilt,pertronix coil,new wires,cap,rotor, the only thing i didnt change was the plugs they were changed last year,its possible one might be bad????...I also thought i found the problem tonite i found a burnt wire and a kinda burnt coil wire so i replaced them but guess what still has that little miss...I give it gas runs great What can this be any ideas????......Thanks
check wiring that feeds 12 VDC to the dist. for frayed or shorting wire, also call Pertronix as there have been issues in the past.
I think 1 year old plugs in a vintage 292 could act as you describe. Just a little bit of oil leaking by worn valve guides can foul a plug easily over a year. It's not that much trouble to clean or replace the plugs just to see.
Thanks for a start i will check the wiring going to the dist. tomorrow,to see if there is anything messed up there....
Yeah i think for the hell of it tomorrow i will change them... Before i put the pertronix in i had a miss too but i thought that was the points being all messed up which they were but i was running it like that for awhile so i could have fouled a plug and if im correct for saying this once you foul out a plug with gas its no good am i right for saying that????
I had the exact same symptoms on a recently rebuilt 170ci Ford six and I was going crazy trying to get it to idle smoothly. I added Pertronix too. It turned out to be a burnt valve. Must have happened before the carb was properly adjusted.
You may have a lean misfire on one cylinder. While the miss is present, add some propane into the carb. and see if it smooths out. Also, you may want to hook up a vacuum gauge and measure manifold vacuum at idle. If the needle is bouncing you may have a burnt/leaking valve or problem with valve train...possibly too small valve lash on one. Beyond that, you may need to scope the ignition and check out firing and spark voltages along with spark durations. Chances are the misfire is always present, but higher RPM will mask it. Kurt
Well to come to think of valve trane problems i have solids that are a little louder then i think they should be will improper valve lash cause this i mean they clack pretty good....I have to adjust them i just really aint to sure on how to do this.....
I think guiseart is on the right road. The fact that the problem clears up with a little throttle tells me that it could be an issue of advance. Put a timing light on the motor (if you don't have one give me a call, I have one and will swing up to your neck of the woods) and set your initial timing a couple degrees forward. See what happens
Joe that sounds good do you know to adjust the rockers i need that done badly they are clacking away more so then i have heard other y-blocks i think there way out of adjustment...and I havent timed it ever, so it could be a timing issue im sure with the pertronix it is different then with the points....
The Y-blocks had a tendency for the oil supply to the rocker arms to get plugged up and stop oiling. The cheap remedy in the old days was a little kit that provided an secondary oil supply to the rockers via a copper oil line,T'd onto the oil pressure sending unit, and running up to the top of 2 hollow valve cover studs(one for each side). They would be a little hard to find now,but it could be done,or make your own. Adjusting the valves is pretty easy.Just follow the pro- cedure in any decent early motor manual. YOU CAN DO IT!!
well seen those units cause problems if'n you don't gap the plugs properly chek that out first on the electronic setups the gap is critical just a thought Al
You did widen the plug gap right? I don't know that the problem would be caused by a too narrow gap but you should be gapped somewhere around .040-.044
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