I have a 66 Mustang with a 289 in it... I'm experiencing some engine problems as of recently. The engine starts and idles perfectly, but when I try to maintain a constant speed it begins to miss, sputter and backfire. There are a couple of things that happened between when the engine ran well and now its crappy state..

1) I installed a Pertronix 1 Ignition with Pertronix coil
2) Attempted to start the car several times before realizing it was out of gas (I'm not as stupid as I sound, my gas gauge dosen't work!)

When troubleshooting I checked the spark plugs and found oil on the tips of the plugs... I've installed new wires and new PCV... before I replace the entire engine by purchasing part after part is there some help out there... anyone...

Thanks!!!!!

 

I assumed you re did your timing, if you havent do that right. Secondly your vacuum advance may not be working. First time your car with vacum plugged than connect it and rev up the engine your timing should advance. its an easy first thing you should check.

 

Take off the Petronics. Put back on what you have taken off. If the problem persists, then you have other issues. Fix them, then put the Petronics back on.

 

That's what I would do. It sounds like you are not getting hot enough fire to the plugs. Double check your pertronix installation.

 

Did you replace the pink wire to the coil with a regular wire. The Pertronix coil is internally ballasted and so doesn't need the resistor wire. If you didn't this would really reduce the spark quality.

 

I think I still have the pink wire there... how much of this wire should I replace? It appears to run back through the firewall somewhere?

 

Okay guys...I fixed it... My vaccum advance wasn't working and I had a bad fuel filter.....runs like a dream!

 

Ahh, Isn't life wonderful whenever things work out right?

 

That's what I hear...
I'll let you know when it happens!

 

You may still want to look at that pink wire also, if I'm not mistaken it goes prettymuch all the way to the ignition switch. If you're running too much resistance, the voltage could be too low or putting more of a strain on your electrical system and have bad things happen. Mine was burnt out and I was just going to replace it with a regular wire and ballast resistor until I could spring for the pertronix, but then I got a little too busy. If you're really going to go for it, I'd reccomend doing a yahoo search for "66 mustang wiring schematic" and you should be able to download the whole thing for free.