MSD gremlin, can't shut off ignition |
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MSD gremlin, can't shut off ignition |
Trekkor |
Feb 27 2005, 12:34 AM
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#1
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
I turn off the key but the engine keeps running.
This is a new problem after adding the MSD. Key turns off the power, I know, because I can hear the fuel pump turn off. It eventually shuts off after turning the key off/on/off/on or revving the motor with the key off. What should I do? Performance is spectacular, except gremlins are tenants. (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif) KT |
Aaron Cox |
Feb 27 2005, 12:36 AM
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#2
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
t dog
i know the answer....i have the hyfire thing right here.... brb with an answer.... i think you need the diode.... lemme check |
redshift |
Feb 27 2005, 12:37 AM
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#3
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Bless the Hell out of you! Group: Members Posts: 10,926 Joined: 29-June 03 Member No.: 869 |
Sounds like power is getting somewhere later than expected. Have you used any old wire, from say... the late 1800s?
Sorry, best I can do. M |
Aaron Cox |
Feb 27 2005, 12:37 AM
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#4
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
yep.... you need the diode! inline....
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Aaron Cox |
Feb 27 2005, 12:39 AM
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#5
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
install diode/resistor in line with SWITCHED positve lead from msd box to igniton switch!
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Trekkor |
Feb 27 2005, 12:41 AM
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#6
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
What diode?
Where me find?...grunt KT |
Aaron Cox |
Feb 27 2005, 12:42 AM
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#7
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
hmmm... you need a diode (lets current only flow one way).... my cdi came with it.... hyfires are better (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif) |
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Trekkor |
Feb 27 2005, 01:08 AM
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#8
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
When all else fails, read instructions.
And, MSD includes the diode in their parts bag. KT |
Trekkor |
Feb 27 2005, 01:12 AM
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#9
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
If anyone has done this *fix*, please guide me through it.
MSD is kinda muscle car and not Porsche specific.( surprised? ) KT |
Joe Ricard |
Feb 27 2005, 06:31 AM
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#10
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
My Hyfire did this last night. Only it was ANDY induced. I needed a switched power. So I figured I could use Andy's version of providing power from fuel pump. So I hooked up the jumper wire from the 4 prong FI to ground bingo 12V. However the dang thing wouldn't shut off.
So I moved the 12v source to share the black purple that used to go to the coil positive with the Compufire unit. Works great. Dark and rainy here today so I will clean up the engine compartment wiring and (IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif) oh yea my tach don't either. (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) So I need one of them adapters. Wife is going to take the plastic pretty soon so I better get it quick. |
Joe Bob |
Feb 27 2005, 08:34 AM
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#11
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
I'm having the same problem,,,,,looks as if the diode goes on the D+ line that goes to the bulb in the charging circuit.....at least that's my answer....everything works AND shuts down when I pull THAT wire. Just no charging....
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0396 |
Feb 27 2005, 08:59 AM
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#12
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Advanced Member Group: Members Posts: 2,046 Joined: 13-October 03 From: L.A. Calif Member No.: 1,245 Region Association: Southern California |
Mike,
I'm not too experience with the electrical stuff, Can you please explain with a diagram? Thanks (IMG:http://www.914world.com/bbs2/html/emoticons/rolleyes.gif) |
Joe Bob |
Feb 27 2005, 09:12 AM
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#13
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
An internally regulated alternator has three wires....one to engine or chasis ground, one BIG RED one that goes to battery, then the D+ wire.....this is also known as the exciter, I think (IMG:http://www.914world.com/bbs2/html/emoticons/blink.gif) .....it has to go thru a powered bulb in the dash.
He, heh, big red one,,,,,exciter....heh, heh....sounds like a cheap porn movie dialogue.... This is one of TWO idjut lights....the other being the oil pressure light. When the ignition is turned on, lights are one.....when engine runs, the lights go out.... NOW, since the fuel pump and a few other items are on the +15 side of the ignition switch....there is a power feed back from the alternator that keeps the ignition switch open....it looks like the D+ line needs a little resistor to stop the feedback. |
0396 |
Feb 27 2005, 09:19 AM
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#14
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Advanced Member Group: Members Posts: 2,046 Joined: 13-October 03 From: L.A. Calif Member No.: 1,245 Region Association: Southern California |
Mike,
Thanks for the reponse. I was concern that my Electromotive would still be running when I tried to kill the motor. I have installed a toggle / kill switch - hot from the battery to the coil packs. I should not experience any concerns right? Have not started it yet, that's the reason for the last question. Thank you (IMG:http://www.914world.com/bbs2/html/emoticons/rolleyes.gif) |
Joe Bob |
Feb 27 2005, 09:21 AM
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#15
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
An on/off kill switch will work....but the diode will also work w/o having to do an extra step to switch anything off....
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0396 |
Feb 27 2005, 09:24 AM
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#16
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Advanced Member Group: Members Posts: 2,046 Joined: 13-October 03 From: L.A. Calif Member No.: 1,245 Region Association: Southern California |
Mike,
Thank you When your in LA , let me know, I owe you a COLD one (IMG:http://www.914world.com/bbs2/html/emoticons/rolleyes.gif) |
Joe Bob |
Feb 27 2005, 09:28 AM
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#17
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
Let's hope it works....kind of funny how more than a few of us have the same problem to deal with on the same weekend..... I had some input from Captain Krusty and some others on the little winky board.....just gotta find a place that has a diode on a Sunday......or else wait..... |
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Joe Bob |
Feb 27 2005, 09:30 AM
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#18
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
Another comment from the 911 board....Rich Herzog...he posts here too...
a diode... the alternator charging current is powering the ignition, IIRC you need a diode in the "switched +12" line. i don't recall which direction it needs to point, but one way will work, and the other won't... a standard 1W epoxy rectifier diode from Radio Snack should do the trick (this is not a critical application. a diode is a check valve for electricity - flows only one way. this is covered in MSD's instruction sheets, which are available online in PDF form. i'll go dig up my 911 ignition folder if i need to, but IIRC it's pretty easy to find the section where they talk about the diode and how it's installed |
iamchappy |
Feb 27 2005, 10:12 AM
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#19
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It all happens so fast! Group: Members Posts: 4,893 Joined: 5-November 03 From: minnetonka, mn Member No.: 1,315 Region Association: Upper MidWest |
The easiest place to put it is spliced into the alt. idiot light wire. or the red wire on the three plug connector from the altenator to the relay board.
Radio shack has them. |
Joe Bob |
Feb 27 2005, 10:24 AM
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#20
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
Since most of the Radio Crap guys are computer geeks w/o auto experience....what diode and what rating?
Trekkor has one but hasn't answered my email yet....prolly still in the rack after a hearty party last night.... (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) |
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