My engine strarted popping last night.

It was colder last night, than it has been when I was driving. Also I did have one day where the engine ran poorly after I washed it, but that was 2 weeks ago. It ran well this past weekend.

I'm far from an engine guru, but I'd pull a few plugs to see if you're running lean or rich. I'm assuming the popping is backfiring and not afterfire, and that you're running lean or the timing has gone off. I'd start with the fuel filter to make sure it isn't clogged and restricting flow, check the float level, the fuel lines, needles and seats (often something will keep them open and flood an engine, maybe something is blocking and restricting flow) etc. ... some carbs have an integral (or in-line) fuel filter at the fuel inlet - check your carb specs - if that's the case, check that it isn't clogged. If you have or can borrow a spare carb, swap it out and see if things change.
Then check your timing to make sure it hasn't gone way out of whack.
Let us know what the plugs look like.

It could also be a sheared distributor gear pin. It wouldn't hurt to pull the distributor and check it. While it's out, replace MSD's spring pin with a proper roll pin, or even better, double roll pins.

5754 is right on EXCEPT:

I'd check to see if the roll pin in the distributor is perfect. If bent or broken this is likely your problem.

The,If all is well there, pull the plugs to see if it shows signs of fuel (more correctly lack of fuel) - if its wayWAY lean fix that.

That's my guess, keep us posted?

"then" if all is well check the plugs.

sorry.

Thanks guys I'll update you when I have the time to look into it. I might be able to pull the plugs today. If I check the distributor pin, then I will have to redo the timing right? That will mean pulling the bulkhead.
Here my current list of possibilities.
1) Timing is messed up because of a sheared pin.
2) Spark plugs are fouled. (missing and backfiring)
3) Lean or Rich (check plugs) I will post a photo
MSD box is bad or badly wired.

I had to drive about 3 miles home, and it ran alright. I accelerated in 3rd at a reasonable rate. It had been popping a bit at idle, but as I drove it seemed to improve. That was an hour after I tried to go for a spin and wanted to accelerate hard and it was bad.

If the choke sticks on and you get on it would it back fire? It actually felt a bit like leaving the choke on on my quad runner, but that doesn't backfire.

The plugs aren't out yet. I am home with my kids. I removed the air filter and discovered that I do not have a choke. The engine idles fine, but when I pumped the gas the bang turned out to be blowing out of the carburetor. My online research suggests timing, or dirt in jets. Any suggestions would be great. I will pull 2 plugs and photo them when the kids are in bed.
Do our distributors use vacuum advance for the timing?

Backfire through the carb can also mean bad plug wires that are misfiring / crossfiring. You really need to start with the basics and work your way up to the more complicated reasons. Do an electrical tune up with new cap, rotor, points (if you have them), wires & plugs. That way, you know these are good. Check all of your vacuum hoses and make sure they are not old and cracked, and any open ports are capped. I recall your brake booster is gone, so that big port should be capped at the manifold, along with the little port on top of the big nipple.

Set up your bulkhead so you can pull it in a few minutes so that is not a deterrent to maintenance. The seat belt bolts can be the only thing holding the decorative cover, and the steel bubble can be held with only a couple of bolts. 5 minutes and your covers are off.

I can try new plugs wires etc. It is frustrating, because it ran fine before. It idles fine and I can slowly rev it up. When I step on it if does it. I did not switch the plug wires so I know they are on the right plugs.
What is this. The plug on the right with 2 wires is very loose. I can't even feel the spades going in when I unplug and plug it back in.

Here is a plug the first 2 are before I cleaned it. There was grease on the manifold, and it got on the plug as I pulled it. The 3rd shot is clean.

2nd

Cleaned

icole, one of every new Pantera owner's first problems is figuring out what the previous owner did, and why. The most problematic area is usually wiring. Sometimes, that requires tearing everything out, sitting down with wiring diagrams (factory, MSD, etc.), figuring it all out and putting it all back in a way that YOU understand it. That usually requires putting everything back to stock, making sure everything works, then re-adding the aftermarket items such as MSD ignition boxes. You also want to install new crimp connectors yourself. That way, you know they're correct and making good contact. Oh, and get rid of those blue wire tap connectors. Those are the blue connectors with two wires on one side and one on the other. They're notoriously unreliable.

Well I don't have stock, and I am a high school chemistry teacher who inherited this car. I don't have the budget to replace parts that work. I will try rewiring if it is not fuel mixture problem, although I will trouble shoot that first.
Ian

I had a stang (68) that suddenly popped through the carb, turned out to be a broken valvespring.
Consider popping the covers and have a looksy.

quote:

What is this. The plug on the right with 2 wires is very loose

That's the voltage regulator, I had wonderful problems with mine when I got my car, but as long as you're not seeing erratic things happening with your Tach, Ammeter (or voltmeter if it's been swapped), then nothing to worry about, just snug up the connections and it should be fine.

Sounds like you've got a laundry list of things to check, if you're in need of some local expertise - lots of deep skills on this forum, but sometimes it helps to have an extra set of eyes on the problem, you might contact some of the guys near Philly (Jon Haas of Pantera Electronics is an awesome guy to get to know), attached is a link to a Google map of some owners, I'd thought there were a few Philly guys there, but the closest plotted seem to be Baltimore MD and Monroe PA.
http://www.mapservices.org/myguestmap/map/PanteraMap

May be a broken valve spring. Visually check with valve covers removed

quote:

take Your Cat to a TRAINED Mechanic Who Does

Get references though, I took mine to a guy who works on many of the classic Mustangs in my area, it cost me a small fortune for little more than a tune-up and the problems I had were only partially solved. It was only when working with some fellow owners that we resolved the worst of the bugs, then me fiddling about changing some parts on the carb and tuning it a bit myself - Kudos to Marlin, his comments to me were on the money for a key source of the problems I was experiencing (no I'm not a mechanic, you as a science teacher most likely have more technical skills than I do). I used to be afraid of carbs, but watched 2 being rebuilt and went home tore into it and she's running better than ever ... I'm almost feeling brave enough to try a leak-down test on my engine this winter - just gotta find a YouTube video to reinforce my understanding of what I've read :-)

Don't despair, talk to a few guys locally - here's a link to the PI regional reps, call someone close to you (Steve in Maryland perhaps) and see if they can point you to someone in the Philly area who either knows engines, or if it comes down to the problem needing more skill than can be mustered locally, they may be able to recommend a reliable shop (I'd still suggest a call to Jon Haas at Pantera Electronics, he's the closest guy to you I can think of, but he likely knows of people closer). http://www.panteracars.com/regrep.html
Or the Eastern Panteras Association:
http://www.easternpantera.com/members.htm

Finally, here's the worst fowled plug I've come across (not mine), the guy running this was shearing distributor pins like there was no tomorrow, but man could his car fly - The shot is here to show you what a tapered plug looks like (just remember what Marlin says about the type of heads and whether tapered plugs are right for you or not).