first startup ignition problem

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87fox72mach

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My Car
1995 firebird rebuilt motor 5 spd dail driver
1987 grand wagoneer plow truck
1987 mustang lx 5.0 work custom engine bay and paint
1972 mach 1 project
well first time start up and I got my engine to fire and run. however the starter continues to run with motor. the iginiton switch, solenoid, starter etc is all new. ok so my key doesn't spring back. so thinking this is my problem I manually turn it back to the run position. car shuts off. so thinking that this problem is caused by my aftermarket new ignition switch on column I put an old riginal I had in. car does the same thing. key spring back to run and it just shuts off. without engine running and key in run position I get no power at coil. throw the NEW switch back in key still doesn't spring back and it will start and run but starter stays running.. ive adjusted the location of the switch thinking it was off and it seems to be correct. im at a loss. im gonna buy a new ignition switch regardless since thew new one I got does not spring back at all. any input? do I have a bad fuse link or something? new coil new dizzy new ignition switch etc

 
When looking at solenoid from driver side. On left I have positive cable. And a fusible link. Next little post I have red ignition wire. Next little post I have yellow 90 degree elbow then on big rifht post I have starter cable

 
Every pic I see is exactly the same as mine. Red blue wire on little post that's towards the front of the car

 
Red blue is on s terminal

 
Sometimes when the large wire lugs are secured/tightened the post spins within the plastic housing of the solenoid. I've seen it a few times where it could have your symptoms.

 
Just put another new ignition switch in. When key is in start mode eng8ne starts. When it springs back to run. It shuts off

 
When I run position should I be getting voltage to coil? Because I'm not


I do have a volt meter. Where do I hook to?


I ok replaced solenoid. Now I got power to coil with key in run position. But motor still dies when I move key from start


Ok scratch that no power at coil with key in on position. I had meter eflippd around

 
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I'm no Midlife, but I'll try and muddle through the explanation.

When the key is in the "start" position the only wire that has power from the ignition switch is the wire to the small "S" terminal on the starter solenoid. So initial test is to set meter for DC voltage, ground the negative probe and clip positive to the S terminal and turn the key to start-you should get 12+ volts. If you want to keep the car from trying to start, just unhook the wires from the large post on the right and set them out of the way.

When power is applied to the "S" terminal, the starter solenoid closes. When closed the large terminal to the starter and the "I" terminal to the coil gets power.

When the ignition switch is shifted to the "Run" position there is no longer power to the "S" or the "I" terminal.

Your coil and distributor get power from the engine wiring harness.

 
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Ok bigg terminal has power 12 volts when I turn key. When key is back in run position. I terminal has no power. Only powered at I terminal with key in start cranking position


I have a mallory unilite distributor. Mallory coil. A stock replacement voltage regulator. A new solenoid. A after market new ignition switch. Starter is a rebuilt stock

 
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My prior post has some bad info. Both the I and S terminal should have no power in the run position.

Your distributor and coil should get their power from the wiring harness. The wiring from the harness triggers the solenoid and does boost power only while cranking from the I terminal.

I believe your harness feed wire is not connected. It is a large pink wire which is also a resistor wire. I do not know if that distributor and coil need full voltage or not though.

Make a jumper wire from the battery to the positive side of the coil and the car should run. Remove it and it should die. It should not remain connected when you don't have the car running.

If no voltage at the coil, you need to look into your engine harness

 
sounds like you have no run position voltage to the coil.

It may be an adjustment to the ignition switch position or more likely a wiring problem.

Note; Voltage to the coil is supplied via the starter solenoid during cranking.

Paul

 
but if I wasn't getting voltage at coil. the car fires when key is in start position and cranking with starter ill try it tho


Engine harness is a new one. Connected properly at firewall. Where would the pink wire run to?

 
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the solenoid boosts voltage during cranking and then turns off, that's why as soon as the starter is disengaged and you turn back to the run position it dies. That temporary voltage is only being fed during cranking. there should be two wires on the positive side of your coil, one that comes from the ignition switch and one that comes from the coil. Here's a typical diagram of the period

73_74PointIgnition.JPG

 
Well I put 12 volts to coil and now I'm only getting 6 volts out of coil and no voltage at points on distributor


I have ground on intake mani fold. Green wore on negative terminal on coil. Red wore to positive. These colors are on harness from distributor. From my car my engine feed harness one wire goes to positive terminal on coil. On my starter solenoid I have one red wire from battery and a yellow fusible link from the engine bay harness. That's it on positive

 
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