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Unread 05-10-2013, 01:23 PM   #1
spoiler73
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Help with ignition or spark for howell tbi

I have the howell tbi hooked up. I can get it to turn over but cannot get it to stay running. If I keep the key turned and open the ports it will run but the starter keeps turning. I cannot figure out what this can be. Is my ignition not staying on? I also cannot figure where to hook up the purple wire that came with the kit.
Any help would greatly be appreciated.


Last edited by spoiler73; 05-10-2013 at 04:36 PM.. Reason: diagnosing problem
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Unread 05-11-2013, 12:11 AM   #2
NonRubicon
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If you don't have the purple wire hooked up just yet, the setup is incomplete. Might be part of the problem. I'm assuming you used either wire "A1" or "A57" from the computer wire harness as the power source for the computer. If you don't have a switched 12V source it'll stop running when you release the ignition.

Dark outside right now, I'll see if I can get a chance tomorrow to take a pic of where the purple wire goes on the starter assembly. Or maybe someone else will jump in with the answer.
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Unread 05-11-2013, 07:43 AM   #3
spoiler73
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I would greatly appeciate the pics.
Thanks
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Unread 05-11-2013, 10:41 AM   #4
NonRubicon
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Here's where the purple wire goes on the starter assembly:



Here's a diagram to help locate the 12V switched wires in the computer harness:



Per the instructions provided by Howell, you can retain either the #1 or #57 (yellow) wires to power the TBI computer.

You'll want to make sure you keep the power source wire as short as possible. If the computer doesn't get enough voltage it will either run crappy or not at all.
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Unread 05-11-2013, 12:38 PM   #5
spoiler73
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Ok. Where does the other end of the purple wire go?
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Unread 05-11-2013, 03:34 PM   #6
NonRubicon
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The purple wire in the pic is part of the pre-made TBI harness. The other end is already attached to the harness.

Post up a pic of the wire you are talking about. There seems to be some confusion.
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Unread 05-11-2013, 04:07 PM   #7
spoiler73
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Ok, heres what I have. The yellow and light green with black stripe on the duraspark ignition module are not comnnected to anything. The las pic is of the purple wire they sent in the kit. It came loose hooked to nothing. They say it needs to be hooked up.



Ok here is what I have done so far. the red wire to 12 volt crank/run wire. The white wire to ground of coil. The orange wire to battery side of solenoid. The purple wire to starter side of solenoid. Grounded to intake. There is another purple wire they are saying to use? where does it go? I am so confused. I know nothing about wiring.
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Unread 05-11-2013, 04:08 PM   #8
spoiler73
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what pic host do I use? I used photobucket for mine.
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Unread 05-11-2013, 06:31 PM   #9
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Quote:
Originally Posted by spoiler73
what pic host do I use? I used photobucket for mine.
I use photobucket and use the img code
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Unread 05-11-2013, 07:14 PM   #10
NonRubicon
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Not sure what's up with the photo not linking. I use Photobucket as well. However, from your description I know what wire you are asking about.

The small, loose purple wire in question is the jumper wire that the installation manual mentions to use in the ICM connector:



What you do not see in the photo is the splice to connect that jumper wire to wire number 18 from the OEM computer harness.

Question now is - do you have an HEI setup? If so, you don't need the jumper wire because the HEI takes the place of the factory ICM. If you don't have HEI then you should have the following:

Before:


After:


It's basically the Nutter Bypass but Howell gives you a weatherpack pin/jumper wire to make use of the open slot in the ICM connector. Lets you easily disconnect the ICM to replace it, without having to cut wires.
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Unread 05-11-2013, 07:41 PM   #11
Michaelgoesrawr
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MCU= Motor control unit/computer?
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Unread 05-11-2013, 08:18 PM   #12
spoiler73
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Here are the pics. Ok I have done the nutter bypass. What the pics show is done. The black twisted wire in the pics is the nutter bypass. I am so confused as to why it will not stay running.






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Unread 05-11-2013, 10:51 PM   #13
NonRubicon
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Quote:
Originally Posted by Michaelgoesrawr View Post
MCU= Motor control unit/computer?
Yeah. Probably should be labeled "ECU". Got the images from the Adventures Under the Hood site. Didn't feel like recreating them from scratch.

Quote:
Originally Posted by spoiler73 View Post
Here are the pics. Ok I have done the nutter bypass. What the pics show is done. The black twisted wire in the pics is the nutter bypass. I am so confused as to why it will not stay running.
Ok. At this point I would make sure you have the computer hooked up to a switched 12V source that gets power in the "start" and "run" positions. If you still have problems even with a verified 12V switched wire, you can try using a relay that is wired directly to the battery. Use the 12V switched wire to trigger the relay, which then sends 12V to the computer. If the computer doesn't get enough voltage it will either run crappy or not run at all.
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Unread 05-13-2013, 07:30 PM   #14
spoiler73
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Thanks for your help. I figured out what it was. I cut the wire that went to the coil so I had no power going to the coil. Too some thinking to figure it out. Jeep runs good now.
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