Ignition Issue revisited

[erics421]

I know there have been a number of posts on this in the past, but it was kindly suggested that I may get some better responses by starting a new thread. So here we go.

I have been seemingly burning through relays/solenoid (whichever you choose to call it) rapidly - each one only lasting a few months. Jeep starts fine one morning, go to leave work, and there's nothing. Voltmeter says battery is good. Change the solenoid, and we're back in business. After the fifth or sixth time, someone suggested that I may have an issue elsewhere in the ignition system. So, here's what I've done. New module (old one was half melted away), new lock cylinder, new ignition switch, new alt, new battery, and of course new solenoid. Got it to start once, an now just getting the infamous buzzing sound from the solenoid. Voltage across batt. terminal is 12+, voltage at battery side of solenoid same, voltage of "I" post on solenoid is only 6V with ignition on, and "S" post also shows 6V while cranking. If I touch the starter wire to the battery (aka bypass the solenoid), the starter engages immediately and turns the engine over. I know I should be getting 12V on the S and I posts, so why am I losing current? BTW, I have run new grounds acroos this system and checked the connections multiple times to ensure tight fits and metal contacts ("protected" with dielectric grease). Help please - it's extremely frustrating to have her sitting when the weather demmands to have her running topless!!
eric

 

[Torxhead]

I would start with making sure your grounds are good. Like how good is the ground to the relay? Using steel as a conductor is a poor way to do it, But that is the way AMC did it. A wire running direct from one of the relay mounting bolts to the battery negative would solve that issue. A poor ground to the ignition control module is a sure way to fry it. The module is normally grounded thru the black wire going into the distributor. This again is a poor connection, the distributor doesn't need it anyway, it was originally made that way for AMC test purposes, or so i've heard. You could just snip it and run it to the battery ground, some guys just add a direct ground from that wire. Replacing those modules is you get what pay for, the oem ones were the best, but no longer available. I think the best one is made by Echlin available at N.A.P.A., but it isn't the cheapest. You also could have some weak fusible links which are connected to the battery terminal at the starter relay. If that doesn't help it you can at least eliminate that possibility.

 

[steveno]

What he said^^^^^ 99% of my problems have been grounds and loose wires......

 

[IOPort51]

Are you sure the S & I wire s are in the right palaces?

and they are even the right wires??

 

[erics421]

Thanks. I have checked and actually ran new ground wire directly to the negative terminal for all the components involved (relay, module, switch, starter). But for good measure I will check all grounds...again (my dad and brother are electricians and work with both AC and DC, so I have had the ground talk many a time ). I have checked to make sure the wires going to the S and I posts are the correct ones.
I am guessing issue is really centered around not getting enough current to the relay which keeps it from activating the starter. I was careful to mark the position of the switch on the steering column before changing it out, but is there a chance that a misaligned switch would cause the voltage drop?