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Old 12-21-2010, 11:46 AM   #1
Locked1
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What are these plugs for... help?

This is on a 1986 GMC HIGH SIERRA, do I need these I change the truck over to a TBI. Thanks for your Help!!
http://www.flickr.com/photos/57303071@N05/5280004635/


IMG_20101220_205541 by cstites4899

Ok the two prong plug hooks into the vacuum acuator and does what?
One wire has a fusible link for what?
The four prong wire goes where?
I also have a loose ground?

Can I eliminate all of them?

Last edited by Locked1; 12-21-2010 at 03:29 PM.
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Old 12-21-2010, 04:00 PM   #2
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Re: What are these plugs for... help?

did you unplug all that stuff and is your truck running?
im assuming somebody disconnected your computer and installed an older hei distributer or modded the original distributer to not need the computer?

the 4 wire plug goes to the dist. the other goes to the vacuum switch/sensor/thing.
all those plugs go to the computer and distributer.

if you are running an older hei you do not need those hooked up unless you have to put it through an emissions test.
as far as a tbi question goes,, i have no idea because i stay away from those.
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Old 12-21-2010, 04:03 PM   #3
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Re: What are these plugs for... help?

Thanks so much, I've been driving it with TBI for over a thousand miles so I would assume I can cut this crap off as long as it has nothing to do with the 700r4 Lock up
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Old 12-21-2010, 04:19 PM   #4
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Re: What are these plugs for... help?

no the lockup vacuum switch is on the other side of the firewall, almost behind and above the brake booster.

those plugs are not hooked up to anything. the computer is just hanging under the dash doing absolutely nothing.
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Old 12-21-2010, 04:45 PM   #5
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Re: What are these plugs for... help?

Quote:
Originally Posted by Locked1 View Post
Thanks so much, I've been driving it with TBI for over a thousand miles so I would assume I can cut this crap off as long as it has nothing to do with the 700r4 Lock up
if your running a tbi and thats not hooked up your ecm is searching for input
so in a nut shell you cant only run what you want on a tbi system all sensors are conected to each other and it takes all sensors to run correctly and the only way to get around this is to reprogram your ecm

Im not where I can go out and look at mine but I want to say that four pin plug is for the map or the tps and both of those will have an effect on your lock up and fuel econemy
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Old 12-21-2010, 04:47 PM   #6
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Re: What are these plugs for... help?

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Originally Posted by big_b View Post

those plugs are not hooked up to anything. the computer is just hanging under the dash doing absolutely nothing.
thats what IM THINKING!

ifso it must run like dogshot
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Old 12-21-2010, 04:56 PM   #7
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Re: What are these plugs for... help?

it should run fine as long as it is disconnected properly or replaced with the old school hei. the plugs that he has disconnected control the vacuum advance not the tbi or the lock up. if it runs bad, the problem lies elsewhere.
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Old 12-22-2010, 12:29 PM   #8
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Re: What are these plugs for... help?

I am running an external coil no hei, it is now computer controlled electronic advance, pictured is original equipment and the TBI is all seperate. I have been driving the truck for over a thousand miles running like a top. I am more or less just wanting to clean up the firewall. Everything works great just didn't want to regret removing this mess. Thanks so much guys
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Old 12-22-2010, 11:24 PM   #9
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Re: What are these plugs for... help?

Those plugs go to the original Electronic Spark Control on your original 305. Take out the box above the glove box, punch out the firewall grommet and the whole system will be removed. Cut the wires and reuse the grommet to fill the big hole in the firewall.

Where is the TBI computer? Is there another hole through the firewall for the install?
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Old 12-23-2010, 09:51 AM   #10
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Re: What are these plugs for... help?

Thanks so much ElGracho exactly what I was hoping to hear and yes my TBI computer is run through another grommett in the firewall though this might allow relocation of my computer.
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