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 ?

[Tom_T]

Jim,

That sounds like what happened with my 73 2L D-jet every year or so when I lived in HB close to the beach @ 16th & Olive & 16th & Orange - just down PCH from you in Seal Beach.

The salt air would get into the relay board & all the EFI & ignition connectors causing intermittent problems, & I'd have my guy @ Hans Imports clean them all every time he did a tune/valve/oil service (actually Hans suggested it).

You can do the same with some DeOxIt corrosion eater & then some electrical connector oil (Wurth or any brand - DeOxIt makes one too IIRC & sold at Fry's).

BTW - that went away - or not as frequently when I moved up here in Orange with my wife for the couple of years it was still running (83-85) - so IMHO it's the salt air near the coast which speeds up the process.

See it that helps!? (IMG:style_emoticons/default/beerchug.gif)
Tom
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[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....