Intermittent starting, Looking at the coil and Mallory Unilite... Options

[jim_hoyland]

Last week my engine did a deep burp as if the fuel pump stopped, I continued on and thought I had a loose connection at the dual relay ( it's a '75 L jet ). Checked every wire, tightened the connections. Started up on first turn of the key- as it usually does.

Subsequently, it still starts fine: but I' driven a few blocks, turned off the engine and found it won't restart even though the motor is turning over. If I wait 5-10 minutes, it will start fine.

I have the Mallory Unilite and a Bosh blue coil. I performed the Mallory trouble shooting test on the Module and it passes- with key on and the module towers blocked with a credit card the voltage fell to less than 2 volts; and the voltage rose to 12 when the towers were not blocked. The Unilite had the Voltage Guard installed as well.

After another short test drive, same thing happens. Ran fine, at restart, won't catch, wait 10 minutes, presto....we get lift off.

Next I tested the coil ( not sure about this test ) by comparing the voltage at -15 and -1 ( or + and - ) With key on, positive is 12 volts, but neg side is 5 volts ? Does this seem right ? Should I replace the coil ? The module ?, or try something else ?

[jim_hoyland]

Interesting, I'll look at those connectors again. Thanks for your insight. Car is stored in a temp controlled garage. Other cars in thesame garage ( including a VW) start perfectly. I'm concentrating my attention on the coil ( it may be weakening) trying to get some others to chime in on coil issues....