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Discussion Starter #1
I have a 1990 LX convertible that I just completed doing a H/C/I swap on. I got everything back together and now when I turn the key to on (but not cranking the engine), the blue 20 ga fusible link that comes from the starter solenoid burns up. It appears to be fine with the 12 volts to it with the key off. I replaced it with a fuse to test and I am getting the same thing, blows the fuse as soon as the key is turned to on. It worked fine about two weeks ago when I turned the key on a few times to prime the fuel lines and check for leaks around the regulator, injectors and fuel rails while I had easy access to them. Since then I have installed the upper intake (GT40 tubular) as well as all of the accessories, MAF, exhaust, etc.
Now it is burning up the fuse link. It must be a pinched wire, but with this information, where should I start to try and trace and find the issue? My wiring harness is in good shape, so I don't really expect an age issue from brittle wires.
I have some wiring diagrams I can use as well, and it looks like when this link burns up it kills power to the EEC relay?

I appreciate any input and advice on the best way to track down this issue.

BTW, I am running an A9P with a Quarterhorse. I do have another working A9P on hand as well.

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Discussion Starter #2
I have done some research, and from what I can tell in the attached diagram below, the orange/black wire from the EEC relay to power many of the sensors/controls such as the ISC/IAB, MAF, EGR, injectors, etc is on my suspect list. This wire receives power when the key is turned on, and it's source for power comes through the fuse link that is burning up.
Does this look right?

Now to isolate this wire and find where it runs.

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Discussion Starter #3
Ended up being pinched injector wires on #8 by a vacuum connector on the underside of the upper intake. Traced it connector by connector until the short to ground went away, which helped isolate the issue to just the harness for the injectors, TPS, IA, EGR, etc.

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Glad you found it. I hate chasing electrical issues. Now you know to check and doublecheck everything before providing power after big jobs.
 

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Glad you found it. I hate chasing electrical issues. Now you know to check and doublecheck everything before providing power after big jobs.
Most definitely
 
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