Electrical cutoff switch & resistor question
#47
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Gotta bump this one again... having a no start issue. The car turns over but will not fire. Wondering if it has something to do with the coil wiring so figured I would verify. I resistance checked the connectors before hooking things up so I know the coil wires are on the proper spade connectors. The source black wire coming from the harness was redirected to one spade on the switch, and the other spade was routed back to the (+) connector on the coil. The green wire stays connected to the (-) pole.
Does this sound correct? Since it is a circuit it doesn't seem that the pair of connectors would have 'polarity'. I don't have a spark tester and it is too late in the eve to buy one tonite. Only working with a multimeter here.
With the main ignition on, where exactly do I check for voltage at the coil... one lead to the pos or neg, one to anywhere on the body for ground? Or does it have to ground somewhere special? Can I check the plugs for spark without a spark tester?
As you can tell, I really don't like the electrical stuff. Give me a busted motor any day.
Does this sound correct? Since it is a circuit it doesn't seem that the pair of connectors would have 'polarity'. I don't have a spark tester and it is too late in the eve to buy one tonite. Only working with a multimeter here.
With the main ignition on, where exactly do I check for voltage at the coil... one lead to the pos or neg, one to anywhere on the body for ground? Or does it have to ground somewhere special? Can I check the plugs for spark without a spark tester?
As you can tell, I really don't like the electrical stuff. Give me a busted motor any day.
#48
Burning Brakes
Join Date: Jun 2004
Location: Livonia, Michigan
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Coil should have power all the time, it sparks once the DME grounds it; one side is always hot with ignition on, other side should not give you any reading untill the DME calls for the spark to fire.
Check voltage between the + terminal on the coil and any exposed metal for ground.
Check for spark the old fasioned way - pull a spark plug lead, stick a phillips screwdriver in there, then hold it near an exposed metal ground on the engine (1-2mm away, like the gap on the plugs) watch for a spark as someone cranks.
Another option is to pull one plug and lay it on the cam tower so you can see the gap. Make sure the the plug is laying so you have contact between the outer threaded body or even the outer electrode and ground.
Check voltage between the + terminal on the coil and any exposed metal for ground.
Check for spark the old fasioned way - pull a spark plug lead, stick a phillips screwdriver in there, then hold it near an exposed metal ground on the engine (1-2mm away, like the gap on the plugs) watch for a spark as someone cranks.
Another option is to pull one plug and lay it on the cam tower so you can see the gap. Make sure the the plug is laying so you have contact between the outer threaded body or even the outer electrode and ground.
#50
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Yep. I also used the 944 spec page as reference.
I'm wondering if it isn't something I did with the push button ignition. There are all sorts of 'extra' wires coming out of the ignition switch that are not hooked up to anything now. Perhaps that is my issue. IT wouldn't be so bad but first thing tomorrow I have an alignment appointment and I need to get the car on the trailer and over there. Sure would be nice if it ran!
I'm wondering if it isn't something I did with the push button ignition. There are all sorts of 'extra' wires coming out of the ignition switch that are not hooked up to anything now. Perhaps that is my issue. IT wouldn't be so bad but first thing tomorrow I have an alignment appointment and I need to get the car on the trailer and over there. Sure would be nice if it ran!
#52
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Yep. I also used the 944 spec page as reference.
I'm wondering if it isn't something I did with the push button ignition. There are all sorts of 'extra' wires coming out of the ignition switch that are not hooked up to anything now. Perhaps that is my issue. IT wouldn't be so bad but first thing tomorrow I have an alignment appointment and I need to get the car on the trailer and over there. Sure would be nice if it ran!
I'm wondering if it isn't something I did with the push button ignition. There are all sorts of 'extra' wires coming out of the ignition switch that are not hooked up to anything now. Perhaps that is my issue. IT wouldn't be so bad but first thing tomorrow I have an alignment appointment and I need to get the car on the trailer and over there. Sure would be nice if it ran!
#53
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I did not have either alarm or airbag in my car to start with. I did chop back a bunch of the radio wires and such. And there are currently next to no switches in the car... just ignition and the cluster. The rest of the dash has to wait til next week.
#54
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Well at the moment it looks like no spark. With all the juice turned on, I get no voltage from coil + to ground. Waiting for my buddy to show up to crank and confirm it with a plug. I know the wiring at the switch is right... there is no power at the source wire from the harness. Pull the plugs and the heads have gas on em so... we know the fuel is there.
It must come from one of the ancillary wires that was attached to the ignition switch. Currently I have the black, the small red/black, and the grey unterminated from the ignition wire bundle. Now I just need to figure out which one is the one.
It must come from one of the ancillary wires that was attached to the ignition switch. Currently I have the black, the small red/black, and the grey unterminated from the ignition wire bundle. Now I just need to figure out which one is the one.
Last edited by schwank; 04-16-2008 at 10:15 PM.
#56
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Actually, just got her running. For some reason I was fixated on the black/yellow when wiring the dash, and wired that into the ignition button wire of the longacre panel.
When you hook up the correct black ignition wire... VROOM.
Again for future reference... this post proved invaluable with the wiring: http://44cup.zeroforum.com/zerothread?id=2515
When you hook up the correct black ignition wire... VROOM.
Again for future reference... this post proved invaluable with the wiring: http://44cup.zeroforum.com/zerothread?id=2515