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Severe stumbling-grrr-next step???

B

blue65coupe

Well-Known Member
Took the car out for a test drive after the e-fan install. After about 10 minutes of driving the car developed a "stumble" at around 2800rpm. Cleared up and kept driving. Then, it got BAD. Even shut off at idle. I'm figuring it's in the "ignition" somewhere and will pull plugs, check wires, possible pertronix issue, gonna look at fuel filter, etc. Anything I may be missing or should look at first? Got the car back home and it had cleared up. E-fan works though :crazy

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Oil around threads on 5 plugs. All ds and 1 ps. Only 1 plug has a hint of burnt oil and it is the one with the most oil around the threads. Safe to assume it's a vc gasket issue and not a ring issue? Try and just tighten or go ahead and replace vc gaskets? Won't fix the miss but later updates for that.

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6/1/09--new plugs and wires and finally got a break in the rain to drive. Same thing. Starts off good, pulls good through the first "gunning", then it misses like crazy under a load. I can let off the gas, get back into idle and it will smooth itself out. Put it under a load and we want to go nowhere. I haven't changed Pertronix, coil, solenoid. New fluids with no oil/water, water/oil. Next thing to check would be.....
 
Re: Severe stumbling-update 1

what? No, direct wired to the battery. It's an adjustable temp controlled (built in relay). The stumbling (miss) took place the other day when it ran a little hot...before the e-fan.
 
Re: Severe stumbling-update 1

"blue65coupe" said:
Safe to assume it's a vc gasket issue and not a ring issue? Try and just tighten or go ahead and replace vc gaskets? Won't fix the miss but later updates for that.
Click to expand...

If the valve covers are light weight tin, put on new gaskets and be sure surface of valve cover is flat around bolt holes.

If they are the heavier aluminum ones, try tightening them down but do not over torque.
 
Coil or electronic ign. controller getting hot? Could have gotten damaged from the overheat, now it is more sensitive. Had that on my Dad's '82 Ford Country Sedan with a 302. Poured water on it when it acted up, all ran good until it got warm again. Replaced and no more problems.
 
could be cracked cap or bad plug wire too. Under load, the volts take path of least resistance. If you can pull it in the garage or somewhere dark, open hood and brake torque with someone standing to the side and see if you have a light show of sparks somewhere...
 
Maybe you are boiling fuel in the bowls. Is the carb hot to the touch when this is occurring? If so, make a 1/8" thick wood spacer with a jig saw and your carb will never again be hot again.
 
I've got a spacer under the carb. I'm gonna check the coil, ign, and cap. I doubt it's a wire per se since they are new and it's doing the same thing. I'm gonna try the brake torque trick but doubt I'll be able to pull much. It likes to spin. Ahhh, what to buy first. I'm guessing replace the pertronix. Thanks guys
 
A different fork in the road; what about a fuel issue? Possibly something in the carb jets blocking the fuel. I've had it happen to me and damn near pulled my hair out going through the electrical side of things. Ended up being a pc of rubber blocking one front jet just enough that when it got into the higher rpm's it started stumbling. I thought it was electrical too until a friend asked if I had checked the Holley jets.
 
Replaced cap, ff, coil. No luck. Carb looks good however, old ff was FULL of stuff. I'm gonna check the new one since it's been on for one drive and see how it looks. If bad, drain tank. If good, pull a compression test just to be sure before I start spending any more money. I doubt that's it but WTH!!! I can stay in the gas and it will bog down like crazy, get a little full power spurt and then back down. HEY PAT, WANNA BUY A COUPE?
 
So have you replaced the pertronix? You might try a set of points just for the heck of it....
 
Not yet. Was not wanting to get to that due to the money and it probably not working. Cheap stuff first you know. While we were doing the rebuild, the guy helping me installed the pertronix. (That was 3 years ago in case you're wondering) That means, I've never done it so I don't know what's going to be involved going back to points. I figure something was removed. Mark mentioned he's running a 6al and thought about that if I have to go that route. I just have to get the pertronix out and see if that's the problem. PIA, PIA, PIA
 
Going to points is not hard. Not much to fix with the pertronix, replace or not. Check the wires coming out of the dist. to the coil. Make sure they have not worn anywhere and causing an intermittent ground. There is also a small pickup that slips over the dist. cam. Make sure it fits snug.
 
Everything with the pertronix looks good. Now, before I replace it, what's involved in going back to points? I will do that before I purchase anything to see if it works.
 
On a standard distributor, you will need the points and condenser. There are three short screws used to hold them in place. Two are for the points, one is loosened for adjustment, the other is used to lock them down. The third is used for the condenser. You will most likely need to buy these, which would look like the one that is used to hold down the pertronix. Length is critical. Looking at the plate with the pertronix removed, it should be easy to see the layout. Once installed and wired, adjust. Forgot about the one screw for the ground wire too. There is a screw where the screwdriver is at.

I will see if I can find a picture which will help you know how things go.
mufp_0505_ign_7_z.jpg
 
Nope. Still a POS. Pertronix should either work or not. No in between so it looks like I don't have to go into that part. I'm going after the entire fuel system this weekend. Tank, lines, everything. We'll see what happens. Anyway, I got a spare set of plugs, wires, cap, button, coil, etc laying around.
 
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