Ignition Switch or TI Problem?

[Bob Grauer]

Occasionally, my 66 427/390 will shut off while running just as if the key was turned off (key still in ON position). When I restart it will fire on a few cylinders, but not start.
This car also has TI which was rebuilt in 99 (new box, distributor, harness, coil). I'm going to replace the ignition switch, but has anyone had this problem?
Bob Grauer 27592

[Mike M.]

Re: Ignition Switch or TI Problem?

Bob first place i would look for electrical dyscontinuity would the the firewall below the drivers side female hood latch, where the headlite harness and the ignition harness connect into the back side of the fuse block. take both ing. and headlite harness off, clean all the pins in the harnesses(believe there are 6 or 8 pins per harness connector. also clean all the pins in the fuse block(sum of all the pins in ign and headlite harness connectors) I usually use a brass wire brush.some use mild acids(metal prep but if you go this route, thoroughly rinse away the acid with copious amounts of H2O then blow dry the whole affair). after cleaning, coat all pins with delco dialectric grease. plug it all back together and take her for a spin. next go to the ing. switch.remove it from the car then you can gently pry back the tabs of the main body of the switch(its pot metal so do so gingerly) and you can then remove the bakelite terminal end. then clean all contacts on the bakelite piece and the metal ring which you will discover under the bakelite. coat these contact points with the dialectric grease(forgot to mention that 3M also has this product and its considerably cheaper than the delco product). After you've explored these areas, check that the ground wire for the TI amp at the radiator core support is grounding out as it should. This ground wire ought to have an external star washer between the electrical connector and the core support. good luck, mmike

[Wayne K.]

Re: Ignition Switch or TI Problem?

Bob,

Mike gives you good advice. I would check the ground for the TI box first as this is many times the culprit.

[Bob Grauer]

Re: Ignition Switch or TI Problem?

Mike,
No luck on the TI ground. I cleaned it up and put a new star washer on it.
I also checked the distributor/TI connections and they seem tight.
It does fire on two or three cylinders but won't keep running. I ordered a new ignition switch (can't hurt to replace this old part). Still has it's original underdash harness. Otherwise, every electrical item in the car seems to be working fine. I'm going to hook up another TI Coil just to be sure that's not the problem.
Thanks and if you think of anything else, I appreciate it.

P.S- Thanks for the lead on Billy Clements. He doesn't have my tag, but at least I know now.

[Clem Z.]

Re: Ignition Switch or TI Problem?

if the dist has a vacuum advance make sure the wires to the pick up coil are not broken from the back and forth movement of the vacuum advance. just use a ohm meter and move the wires back and forth