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rbogh901's Avatar
 
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Quote:
Originally Posted by Jonny H View Post
Yes, number 1, the lowest one with the extra wire.

As a simple test, why not pull that wire with the engine running?
Woohoo. Now we're talking party time. Grab the red wire and pull it with the engine running. Something's bound to happen. What could possibly go wrong?

None the less I think there's real underlying Merit in following this.
Maybe I'll unhook the red wire without it running first. Being that I'm sort of small steps kind of guy. But I like the idea and was able to trace that wire to the tach adapter for the MSD so it's worth a look.
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Old 10-09-2017, 06:53 AM
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One of the 2 wires on the left side should be supplying switched power and the other should be constant power. With ignition off, test each fuse terminal with a voltmeter for 12 volts to ground.
Then do the same with ignition on. Report back.
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Old 10-09-2017, 10:41 AM
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Is the brown/black wire below the fuse panel unplugged?
This is the safety shut off wire for your CIS fuel pump relay. Needs to be connected!
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Old 10-09-2017, 10:47 AM
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Quote:
Originally Posted by timmy2 View Post
Is the brown/black wire below the fuse panel unplugged?
This is the safety shut off wire for your CIS fuel pump relay. Needs to be connected!



Thanks guys. Will do as soon as I can sneak away from family obligations. This whole thing is top secret hush-hush.
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Old 10-09-2017, 12:09 PM
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The brown wire with black stripes mentioned above does appear connected within the connector. The Spade is in decent condition and I pulled it apart pushed it together a couple of times to convince myself. Thanks.
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Old 10-10-2017, 07:54 PM
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Quote:
Originally Posted by timmy2 View Post
One of the 2 wires on the left side should be supplying switched power and the other should be constant power. With ignition off, test each fuse terminal with a voltmeter for 12 volts to ground.
Then do the same with ignition on. Report back.



Well, I checked. They are both on all the time. Ignition on or ignition off they stay on. Same voltage as I am measuring at the battery terminals. So apparently the switched one isn't.
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Old 10-10-2017, 08:20 PM
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Has the ignition switch been replaced? The ignition switch has 12V hot and 12V switched wires. If one is at the wrong terminal then the engine will stay running (as will several other electronic items).

Worth a check to verify the wiring.
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Old 10-11-2017, 06:45 AM
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[QUOTE=jpnovak;9771943]Has the ignition switch been replaced? QUOTE]


thanks Jamie.

Not to my knowledge. The car is new to me. Clearly the PO had no idea what to do, see the jumper cables running to a shut off switch tunneled to the dash vent in the earlier photos.

I got all crazy and pulled the connector from the ignition wires under the dash. It is circled in blue here in a photo I poached, not my car but used for illustration purposes, mine stayed in the car. Doing that cuts power to the number one fuse in the engine bay, the one Timmy asked about with the wire added for the MSD in the photos above. It also stops my fuel pump from running. Power to the number 2 fuse stays on.

Makes me think the ignition switch isn't switching but maybe that's jumping to conclusions. Yes? No?
You can't believe everything you think.


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Last edited by rbogh901; 10-11-2017 at 09:39 AM..
Old 10-11-2017, 07:50 AM
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Bottom 2 fuses are likely jumpered on the back. Move the middle one up to the top where it normally should be. Test again
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Old 10-11-2017, 09:16 AM
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Quote:
Originally Posted by timmy2 View Post
Bottom 2 fuses are likely jumpered on the back. Move the middle one up to the top where it normally should be. Test again
Ok. I can try that. But it doesn't make sense since power to the bottom (#1) fuse is cut when I pull the ignition wire from the dash but the middle one (#2) remains always on, so they can’t be bridged I don’t think. I forgot to mention that in that post above. More information helps doesn't it? Thanks Timmy.
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Last edited by rbogh901; 10-11-2017 at 09:40 AM..
Old 10-11-2017, 09:38 AM
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Someone has buggered something up somewhere.
Normally the constant hot goes to the top fuse and switched hot to the bottom fuse.
Center fuse is bridged to one or the other depending on the year. (As has been mentioned by others)
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Old 10-11-2017, 10:34 AM
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Quote:
Originally Posted by timmy2 View Post
Center fuse is bridged to one or the other depending on the year. (As has been mentioned by others)


Well, by golly you are right. The middle fuse is bridged to the top one, the one marked #3 and not currently in use, no fuse in that one. So those two would be always on if it was being used.

Meanwhile the bottom fuse, #1, with the lead to the MSD, loses power when I disconnect the connector at the ignition switch. It might be that the ignition switch is always on until I pull that connector. Could this account for both the fuel pump and engine run-on?

Seems like it to me but this is the first I’ve ever dealt with electrical beyond putting bulbs in my headlights.
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Last edited by rbogh901; 10-11-2017 at 10:55 AM..
Old 10-11-2017, 10:52 AM
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Quote:
Originally Posted by rbogh901 View Post
Well, by golly you are right. The middle fuse is bridged to the top one, the one marked #3 and not currently in use, no fuse in that one. So those two would be always on if it was being used.

Meanwhile the bottom fuse, #1, with the lead to the MSD, loses power when I disconnect the connector at the ignition switch. It might be that the ignition switch is always on until I pull that connector. Could this account for both the fuel pump and engine run-on?

Seems like it to me but this is the first I’ve ever dealt with electrical beyond putting bulbs in my headlights.
When I time the ignition on early cars, I usually clip my timing light onto the left of the fuse block, effectively bridging the terminals.

It has become my party trick to then take the ignition key out with the engine running and hand it to the owner. Gets 'em every time.

Also if you fit a 3.2 Carrera rear fuse block to an early car you get the same thing as all three terminals are bridged.
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Old 10-11-2017, 11:15 AM
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Hey, good times, thatís what mine does. Just pull the key and walk away. Does the fuel pump keep going too? Or is that cut with the key pulled out and the motor eventually sputters?
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Old 10-11-2017, 12:41 PM
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Originally Posted by rsscotty View Post
Simple test to see if this is part of your problem. Or if it is in the MSD wiring.
Disconnect the red wire to the CDI and see if switched power now works as it should.
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Old 10-11-2017, 12:47 PM
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Hey, good times, thatís what mine does. Just pull the key and walk away. Does the fuel pump keep going too? Or is that cut with the key pulled out and the motor eventually sputters?
Last time I did this trick was on a 73.5 CIS car so fuel pump must have kept running.
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Old 10-11-2017, 02:20 PM
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Fuel pump will run with ignition on if the brown black wire below the 3 fuse panel is disconnected.
Early CIS didn't have that feature and will run as long as there is power in the circuit.
Either from the ignition or a back feed from the fuses like Johnny's trick.
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Old 10-11-2017, 02:28 PM
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Simple test to see if this is part of your problem. Or if it is in the MSD wiring.
Disconnect the red wire to the CDI and see if switched power now works as it should.
Ok, sounds good. Iíll try it.
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Old 10-11-2017, 03:00 PM
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Fuel pump will run with ignition on if the brown black wire below the 3 fuse panel is disconnected.
.


Will it run with the ignition off? Did you mean off here? Trying to figure out the fuel pump run-on problem too.
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Old 10-11-2017, 03:09 PM
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If you have a back feed of 12 volts (it appears you do) yes.
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Old 10-11-2017, 03:12 PM
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