318 Stalling at 45 mph

-
Brian

Brian

Active Member
Joined
Apr 3, 2006
Messages
36
Reaction score
1
I have a 1972 318 mostly stock but with Edelbrock Performer manifold and Edelbrock 600 carb. I recently put in a Pertronix coil and electronic ignition system. Since then, I'm assuming that it is related but maybe not, the car sputters and stalls every time at 45 mph. When in neutral or park, it does not stall ever, even when reving the engine, only stalls when in gear. Any ideas on how to fix this?
 
Check coil ground, You may have to take some of that pretty new paint off. Which system do you have, ignitor-II-III?. The laters provide overload protection, and will shut it down. Strange, only under load,@ that speed. MP kits provide an upgrade with volt. reg. and ballast res. Strange that pertronics doesn`t. Maybe @ that speed @ load its throwing to much and shutting down? But seems if you simulated the rpm @ 45 it would do the same. Tryed reving steady @ 2 grand for 5min. see if it heats up and shuts off ? good luck
 
the coil doesn't have a ground, it completes its ground though the ignition module, which causes the coil to fire. I'd make sure all your connections are tight...even those on the spark plug wire.
 
Could also be running out of fuel from a bad fuel pump, partially plugged filter or lines. Does it pick back up after you take the load off the engine?
Easiest way to check it... either shut the igniton off when it dies, stop the car and pump the throttle while checking for fuel coming out of the squirters OR hook up a temp. fuel pressure gauge and zip tie it to the cowl vent ot wiper.
You use a lot more fuel when driving the car compared to just revving it up.
 
Check the ignition connections. Sounds like a loose wire somewhere.
 
It is an ingnitor II and a new Carter fuel pump. The pump is getting 4.5 - 5 psi but I have not checked it while it is under load. I'll check all of the connections and when the snow melts, I'll put the old coil back in, take it for a drive and see what happens.
 
Oh yah, when I hit ~45 mph, it stumbles and then I lay off the gas and it won't get back to normal for a few secconds. One or two times, I had to coast to a dead stop and had to let it sit for a minute more before it ran normal again. It never completely died, but no power at all.
 
you say snow? how cold is it?have you checked to see you don't have dirt or water in a slushy state in the tank? these things sound kinda silly till it gets cold. maybe the sock on your fuel pick-up is clogged. but i'd say fuel delivery related.IMHO.
 
The coil is a step-up type transformer, 6-8 volts in and 20,000+ out depending on the type. The primary winding and secondary wiring are grounded to the case and thru the bracket to the intake. You need to be sure you have a good ground. I think it's a fuel problem though.
 
goldduster318 said:
the coil doesn't have a ground, it completes its ground though the ignition module, which causes the coil to fire. I'd make sure all your connections are tight...even those on the spark plug wire.
Click to expand...

Robbie2734 said:
The coil is a step-up type transformer, 6-8 volts in and 20,000+ out depending on the type. The primary winding and secondary wiring are grounded to the case and thru the braket to the intake. You need to be sure you have a good ground.
Click to expand...
Glad I got some back up. Because after 2 days cleaning every ground strap and mount points, and bulkhead connectors,etc. racking my brain, replaceing ballast:angry7:. I cleaned coil bracket and bolted tight, it fired right up. But after further clues/posts, I`m also thinking fuel related. Water/condensation, and possibley fuel filter has caused these synptoms, in my car also. Brian, keep us informed of fix, Try a bottle of drygas, and a new filter. good luck
 
Has the car sat for very long Brian. The shutting down thing could be Fuel. But it also might be a bad ignition module. If you have a heat gun try heating up the module with it idling to see if it will stall. As for the carb, pour some carb cleaner down the overflow tube and let er sit.
 
Possible vent on the fuel tank plugged? When it stalls, get out and take off the gas cap. If it has a lot of vacuum in there it may be plugged vent hose or bad cap.
 
All I know is I have a very similar problem, only with a 64 273 Dart. I just had the points and condenser done, as well as a new rotor, cap, plugs and wires, and even the coil, my fuel flow is fine (new pump, filter, even some of the lines) and a freshly rebuilt carburetor, and still this problem persists.
So, if I figure it out, I will let you know.
More likely, someone will figure it out FOR me!
 
Uh oh...Two of you with the same problem? Its a conspiracy I tell you..They are out to get us! Keep driving!
 
I'm still trying to figure this one out. Here are some of the things I did:
I have new gas in the tank with a carb cleaner.
Put the old coil back in.
New fuel filter.
Took fuel cap off.

Is there anyone in the area (Chicago/Schaumburg) who would like to help? If not, does anyond know of a good shop that I could take it to (in my area)? It seems like everyone I talk to does not want to work on a car with a carburator and points.
 
Hey Brian: Drop your gas tank and take out the float mechanism and you will find a sock on the bottom of the pickup tube. Big chance there is a blockage there. You can do it. Need any info just sing out. If the sock filter is plugged , cut it off, then at a couple of locations along the routing of your fuel line place a couple of inline fuel filters in an easy to get to places. Change em as needed. You should have one in the engine bay area by now anyway. While you have the tank out clean it real good and dump out the gas and see what you come up with. Might scare ya.
Small Block
 
If ya want to save some time in diagnoses: put compressed air into the fuel line from the tank and either blow out the sock or blow it off. If the engine works better you have found the problem. If not you can choose to leave the sock for now or drop the tank as small block suggested. Suggest you leave the cap off the tank.
 
You must log in or register to reply here.
-

Back
Top