Me again, weird stalling question!!!

[Anonymous]

1965 200ci mustang, auto.

My car WAS running perfect after changing over to an electric fuel pump and cleaning out the lines and tank. I rebuilt the carb and set everything to spec (for a stock setup). The car runs perfect and then runs crappy out of nowhere!

I found out some more info from the people I bought it from, it had a full rebuild of the engine and tranny. It has a Hi-PO cam installed. So I do not know the new alignment specs. I set it to 600RPMs in gear. It is about 750 in park
(runs too rough below these RPMs). The carb and anti stall dashpot are set to specs from the rebuild kit, but variations don't help my problem at all (I've tried leaner and richer with no avail). I also replaced the PCV valve.

The timing I believe is set at 14 initial with the Petronix kit. New wires and plugs set to .040. The car runs perfect and then sometimes out of nowhere it starts running crappy and stalls with the throttle half open, but not if you ease into it just when you jump right to half throttle, even in park.

It has never done this before and the accel. pump is giving it a good shot of gas still. I checked before and after the running bad. The kickdown cable is has been looked at and set also. I am at a los to the problem... you start it up a few minutes later and it is fine again.

Oh, the diaphram on the distributor is good also. :

 

[The Plankster Prankster]

sounds to me like it might be flooding. i had a carter YF that would do that a lot, same symptoms, wouldnt run consistently - it would flood at least a couple times on a good day, at least. mine was also right after a carb rebuild. i set the float to every possible position and played with it for a few thou miles. then i replaced it and gained about 3mpg and a whole lot of reliability.
...but i'm a big-block man, what would i know
--josh

 

[Mercury Mike]

Autolite 1100? Check the acceleration pump!

 

[fordconvert]

I have not done the petronix kit so I dont know for sure but is it possible that something is wired or aligned wrong? I just did a duraspark conversion on mine and had the pick up coil wires reversed. The thing ran pretty good off idle and would idle smooth but had these random stumbles. I noticed that when it stumbled the spark droped. Turns out that because of my goof it was fireing the coil when the rotor was between the posts so sometimes it could make it sometimes not. Did a lot of head scratching on that one.

Thought I would mention it incase its possible to have the same issue with the petronix.

 

[Anonymous]

Had a similar problem a few years back when I also converted to a petronix setup. The car idled fine but if I hit the gas pedal hard it would occasionally stumble and sometime stall outright. The strange thing was, like yours, if I feathered the gas pedal I could raise the rpms without any problems. I couldn't help but suspect the petronix because I didn't have the problem before with the points.

I removed the petronix and put the points back in and much to my surprise I now had the same condition with the points! I finally found the problem but not until after I had pulled most of my hair out! When I was installing the petronix I noticed that the power feed to the coil was just wrapped around the coil terminal. I didn't like the looks of that so I put a crimped connector on the end of the wire. The wire was loose in the connector! Apparently the vibration, when you hit the gas hard, would cause it to loose connectivity and thus the stalling and stumbling. I removed the connector and just wrapped the wire around the coil terminal, like it was originally, and the car worked fine!

For what it's worth

 

[mkgcars]

Couple more ideas (I suggest them all the time - did wonders for my car).

Could check the fuel pressure. Maybe it's periodically overloading the shutoff needle at the carb. Can always try lowering the float a 1/32. -Especially if you think the fuel pressure is on the high side or a bit over spec.

And see if there is a gap between the accel pump rod and the diaphram, and also make sure its not applying to much pressure on the diaphram when you're off the throttle.

matt

 

[cfmustang]

If it is fuel pressure, a fuel pressure regulator may help.

Those of us with Webers need to use them, but I don't know about Autolites. It really made a difference when I added mine.

 

[Anonymous]

Had the same problem a couple months ago and was on here trying to find the problem! Well the problem was the pertronix ignition wires were loose! We took them off re-crimped the wires and put them on again and made sure all the other ignition wires were connected correctly and made sure none were loose.... i now can hammer the gas and it responds immediately.... i guess when you eased into it, the wires didn't jump around as much as they do when you stomp on it...so my advice on the subject, is recheck all the igniton wires...something is loose or touching another wire or something like that! Have a good one!

 

[Anonymous]

The wire to my ignition coil is bare now and I got the same crap. I did find a vacuum leak though, helped with the running up and down (but that was so slight I didn't notice the difference until it was fixed). I replaced all my vacuum lines and used little clamps on the ends of them. I checked the plastic fittings on the cheapo power brakes master and no leaks there.

I have a slight miss at about 1/3 throttle, and if I jump from no throttle right to 1/3 it sputters or dies almost every time. If I slowly give it the gas it runs fine through the whole engine bandwidth.

I have also tried playing with the anti-stall dashpot, but there doesn't seem to be any effects there.

I do have the picky autolite 1100 carb, but it has been rebuilt and set perfect to the specs laid out in the kit. I have deviated with the lean/rich screw and the problem I'm having doesn't seem to be effected by that either. The accelerator pump is giving it a clean shot, it only sputters or dies at a quick 1/3 throttle.

Also, I tried putting the points back and have the same issue.

EEEEKKKKK

 

[wallaka]

Ahh....crimped wires. You need to invest in a soldering gun and some heatshrink, you wouldn't believe how many problems that will solve. I don't use those little crimp connectors for anything anymore.

 

[Anonymous]

Another thought

You mentioned in your original post that the diaphragm in the distributor was good, but have you actually verified with a timing light that your vacuum advance mechanism is actually working?

 

[Anonymous]

I tried to test for proper operation yesterday and today... but I have a problem...

It is running perfect again and I can't get it to act up. It is definately an intermittant problem :roll:

 

[fordconvert]

How long has this been doing this? Time and miles? Is it possible you got some bad gas?