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General Tech Voltage Drop and Starting Problems

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CJD said:
I once had a problem of my car dying at odd times...and sometimes it would fire right back up and others not. It turned out to be the ignition switch.

These are very simple cars. Next time it dies, try a hot wire from the battery to the coil...that will eliminate all the wiring, switches, regulators, fuses and wiring. If that does not get you running, then you have it narrowed to the coil and distributor.

I would not discount vapor lock, but vapor lock does not normally kill you instantly. You usually get some sputtering, and even when trying to start it will normally pop every so often. Add that to the fact it would not restart for many hours, and vapor lock should be down the list for now...that is so long as you are positive the fuel pump is working??
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Each time my car stalled and showed the symptoms, I connected a multimeter to the ignition wire side of the coil and wiggled all of the wires on the back of the ignition switch and at the coil, itself, and I even jiggled the key around. I didn’t notice any issue at all.

Someone did mention to me that a faulty ignition switch can be an entirely internal matter, meaning internal to the switch, and that I would never be able to identify identify the problem by wiring issues, but only by replacing the switch with a new one. For example, what if something internal to the switch is defective at the post leaning to or powering the ammeter gauge?

I might just try that and see what happens.
 
CJD said:
Condenser. The new ones have a terrible reputation.
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If this is a TR3 issue.....do you have a ground wire running from the Neg side of the Battery to the engine? I had hard starting issues on my 3 until I took Poolboys advice and ran a ground wire to one of the bolts that hold the cover for the old fuel pump when I switched to an electronic pump. The existing ground wire to the firewall and the braided ground wire near the steering box were not enough to give a good ground. With this fix I had a BIG improvement in starting. Not sure if it's an issue with TR4's and 6's though.
 
I would still jump from battery to coil next time it happens.

The reason is there are a lot of electrical problems that provide a slight connection but for whatever reason cannot provide the needed amperage. That means the multi-meter may show voltage, because it draws no current, but the circuit cannot provide amperage. The beauty of the jumper is it is simple and will immediately rule out more than half the possible components.
 
John I really like the hot wire idea. I have not done it for a while. If I remember, the procedure was a wire from the distributor side of the coil and hot side of the battery, but if you are positive ground, hook to the negative side of the battery. What a great idea for finding out if the problem is in the key or the wiring.

Steve
 
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