Hello, this is my first time asking for help ! We just recently had a rebuilt 455 put in our ‘69 Skylark and stopped for gas. Restarted no problem when then leaving the gas station and accelerating into traffic it puttered then we lost all power. No brakes or steering . Narrowly avoided getting destroyed by a tractor trailer. Car restarted and we proceeded until I parked it for 10 minutes. While merging into traffic, without sputtering, engine cuts out AGAIN. This time absolutely nothing. Complete no power. Won’t even click to turn over. Electric fans won’t start, then suddenly, with a boost it starts. The mechanic had just recently replaced the water pump and re-timed the distributor ? Does anyone have any ideas ? Any help would be greatly appreciated. Have a great day !
My first thought would be to check the connections of the cables and wires at the battery, starter, and grounds (specifically the negative battery cable connection at the motor). make sure they are all clean and not loose. Heat will make a bad connection worse.
Same as above. Wouldn't hurt to look at the rotor button, mine went bad all of a sudden on the highway and poof, no power & luckily we coasted to the shoulder. Could have burned through and opened a fusible link somewhere...Good luck!
Also look for loose wires on alternator. Systems seem to indicate a loose wire some where, especially since the engine was recently installed.
There's an ignition wire that goes from the fuse block to the starter that applies full 12 volts to the ignition coil while the more is being cranked. There is a tap off that wire (at the firewall behind the motor) that goes to the ignition coil. After the engine starts the voltage is reduced to 6-8 volts at the coil. If that wire is intermittent, the engine would stall and maybe restart, maybe not.
Did you check if the headlights (only) still work? Time to post the good old fusible link image again:
It might still start if the link is not totally gone, the movement of the engine will finally jerk it apart, just like happened in the story of the OP.
I did check but nothing was working. Apparently they had installed a new MSD box and wired it directly to the battery with no switch so it was draining the battery. I will have them check the fusible link. Thank you
I have an MSD box in my car. There are 2-each 12V connections. One goes to a switched 12-volts (like from the fuse box, on/off with ignition switch), and the other is supposed to go directly to the battery. That's crazy if they wired them both to the battery!!!