Hi guys, new owner of an 89 GTA restoration project (5.0 TPI manual) and starting to tear things apart a bit since it won't start since today. (Started fine and drove home a few days ago, today can't hear fuel pump prime) have a few questions. First, let me admit I am clearly lacking a basic education in auto electronics, period. SO, please see the pics below.
the 1st pic is in the fuse panel and is a jumper wired to a green with white stripe on one side and solid purple on another. No idea what it is. 2nd, there is a 10A fuse wired directly to the battery and other end is spliced (poorly) into an orange wire going to a relay on the firewall.
Any feedback is appreciated.

 

I don't want to be mean or minimize the seriousness of your situation, but...

Asking us out here to look at what some HACK did to our wiring, is only going to lead to abuncha wild-a$$ guesses. NONE OF US was there (I hope) at the time whatever MORON thought s/he was going to "improve" the car by HACKING on it that way.

Best we can do is, identify whatever FACTORY wiring we can see. Whatever HACK JOB wiring was added, ... who knows?? Just because the wires they put in are [whatever color], do you HONESTLY think that means ANYTHING??

That said, whenever you can identify FACTORY wiring, the thing to do is, GET RID OF any "improvements" some PO made to it, and PUT IT BACK like it came. Don't even BOTHER trying to second-guess what they thought they were "accomplishing" by DESTROYING the poor car, which couldn't even fight back.

FACTORY white & orange wires together usually means an interior light bulb. Seeing those together and taped up means there's probably an entire light fixture missing, and some part of your car that's dark at night when you open the door.

FACTORY green w/white stripe is the radiator fan relay wire. Usually goes to the temp switch in the pass side head, to somewhere in the ECM, and maybe somewhere in the AC circuitry. Most likely somebody thought they were "improving" the cooling system by HACKING something (probably a switch) into that circuit.

Can't begin to guess what the 2 blue wires are, or the thing that they're HACKED onto. You'll just have to trace them and see where they go.

I think the relay with the foreign red wire HACKED onto it is the fan relay, but I'm not sure. Usually that relay would have a pink/blk, a green/wht, a red, and a red/blk on it. The red & red/blk should be VERY LARGE GAUGE wires. Unlike the HACK job red wire that's there, which is small, and therefore not surprisingly, is burnt to a crisp.

The fuse in the purple wire and all that, I can't begin to guess.

I'm sorry, I should have mentioned, some of what you show is HACK JOBS. Are we clear what that is? Do we understand how that's WRONG? Do we know what we need to do once we identify HACK JOBS? Not much point in coming in here, or anywhere else, and asking US what some HACKER "intended" or what they thought they were "improving"; best we can do is to tell you, GET RID OF IT ALL, and put it back like it came. Fix what's broke as you come to it, but GET THE HACK JOBS OUT OF THERE first and foremost.

Getting the pine needles out of everything and [gasp]taking it ti the quarter car wash and getting the 30 years of FUNK off of everything [/gasp] would also show the rest of us out here that you actually CARE about it, and would help towards motivating us to help you.

 

If I were a betting man , I'd bet you a dollar that the 10A fuse HACK (Yeah Sofa , I said HACK in caps just for you ) came about because the fender mounted fuse that feeds the orange wire it's power got blown and someone with just enough electrical knowledge to be dangerous "restored" power to the wire with that HACK (oops I did it again) because they were clueless about the infamous fender mounted fuse .

Sound about right to anyone else here but me ?

 

I think you are right since the HACK red wire is spliced into orange going into the relay, which if I am not mistaken and can verify later - runs to the infamous fuse.. This fuse? see pic
BTW - This 20a fuse was indeed blown - I have since removed the 10a HACK fuse red wire circuit and replaced the correct 20a fuse. Still no fuel pump running...

 

Great , that's a good starting point . Now , take an automotive 12V test light (available for cheap at your local autoparts store) and verify that you do indeed have power on both sides of the fuse (as measured to ground) . My preference here is for a test light that actually contains a little 12V incandescent light bulb VS an LED or using a modern voltmeter , if it lights the bulb the power is good VS sometimes modern meters can read through the leakage current of a poor connection and show a false 12V reading which quickly disappears when a real load (like a light bulb , or perhaps your fuel pump) is put on the circuit . If you do have power on both sides of the fuse the relay would be the next check , does it click for a couple of seconds when you turn the key on without trying to start the engine ? As in , key on , relay makes one click , two seconds later a next click is heard (the relay engaging then disengaging to command the two second prime) . If you hear those sounds take your test light to the large tan/white wire at the relay and turn the key on again from the off position (make the relay click) and see if that wire has power for two seconds . Piece by piece like that you gotta follow the path from where the circuit's power originates to where it's lost , to see why the pump won't run . Your troubleshooting may well just lead you to discover that you DO have a good 12V path to your fuel pump and the pump itself has died , and if it has don't you DARE consider hacking a hole to replace the pump and then come here to tell about it , you'll be literally roasted alive and eaten as a crunchy after wrenching snack by the TGO community

This wiring diagram is for a 1989 six cylinder , but the fuel pump wiring is identical to your eight cylinder . Of note is that the relay and the fuel pump switch that's activated by the engine's oil pressure are wired in parallel , so a check of relay wires and the fuel pump oil pressure switch's wires would be a good thing here .

 

The relay does click, but it seems like it might be the wrong one clicking - 2 things though:
1. I definitely hear 2 clicks when rolling the keys forward - I haven't visually inspected/felt yet if it is indeed that relay.
2. I tried jumping the fuel pump from terminal G on ALDL last night and the fuel pump didn't run. But a relay clicked whenever I supplied 12v, and from what I know and could hear/feel - It wasn't the fuel pump relay - It was the MAF relay? (First oval relay next to the rectangular fuel pump relay on firewall (middle of the 3))
I am getting seriously concerned about what the PO did with the wiring here, have you had a chance to look at that jumper that was installed under the fuse panel (one side green/white stripe the other solid purple) pic in the first post))
I am committed to getting this fixed asap!

"and if it has don't you DARE consider hacking a hole to replace the pump and then come here to tell about it"
LOL, this morning before work, i jacked the rear of the car up to get access to the fuel pump 3 wire connector between the 2 rear seats and after reading about the "hacked" holes for fuel pump access i thought, what the heck? Pulled the rear carpet up and sure enough there it is in all it's sawzall glory... I was already getting mentally prepared to drop the fuel tank! Well guys, I am saving what I can, can't wait to show off the before and after after sorting out all this other S*** that the PO did.. (Did I mention he spray-bombed the entire car with tremclad rust paint primer gray...) Yeah, I spent 6 hours with a water bucket and razer taking the overspray off all the glass, not to mention wetsanding all the paint off the tailights as well (at least they look good as new now after polishing)..
Anyways getting back on track - I will follow your advice OrangeBird, and start tracing back with a test light starting at that fuse. I was also planning on just running 12v directly to the fuel pump to test - seeing how I have easy access... if I can force it to run direct and rule out right away that it is not the fuel pump or connection @ pump in tank itself - The PO said he just replaced the fuel tank and based on some of his other S*** work I wouldn't be surprised to find a clogged screen and loose connection in there as well.

 

Yes indeed it sounds like ya got some serious work to do putting that car back right again , I'm glad it sounds like you've got the determination to fix it up properly

Since you searched and found all the fuel pump hole threads that means you saw the pitchforking , torching , and cannibalization of the folks who favored the hole , and so you know why I made light of it . I do favor not cutting a hole myself (My car is like South Park , Bigger , Longer , and Uncut) but since you've already got a hole my best suggestion would be to search the threads started by the member "Tibo" here at TGO , If I recall correctly he found his car had been cut by a previous owner and he then manufactured a proper access hatch that even I would be ok with having on my own car .

 

If you feel confident in your ability to run power directly to the pump by all means try that , just remember when you unplug that connector under the back seat there are three connections , one is a ground connection , one is the pump and the other is the gas gauge . With the connector unplugged you'll have to run both power and ground to the connector going into the tank to see if the pump runs , in other words there is no other ground for the pump (or gauge) besides the one in that 3 pin connector . Polarity matters , and if you mistakenly put 12V across your gas gauge sender you will destroy it instantly .

 

Oh , and , as to the connector with the blue jumper , sorry I didn't mention it sooner but I'm pretty sure that is supposed to connect to the switch on your clutch pedal that will allow the starter to crank the engine only when the clutch is pushed in . With the car in neutral , and not pressing on the clutch , if you turn the key to the start position does the starter engage ? If yes , that means the switch at the clutch pedal likely went bad and the PO jumped it because , well , because he was a flippin hack .

Thank You for tuning into another exciting episode of "Automotive Forensics ; The sad tale of the butchered Bird"

 

So I traced everything back and confirmed 12v for the 2sec open relay when turning keys at the wire connector mounted behind the rear seat. Wiggling the wire connecting going from there to the yellow head on the pump will intermittently allow the pump to prime. So there ya go
I have no working gas gauge though so I will be pulling the whole sending unit out to inspect and most likely toss and replace, Going to need additional parts though as the PO didn't install the gasket properly and destroyed the mounting ring in "replacing" the fuel pump a month prior to me getting it.. Trying to find a lead on the wiring harness that runs from the yellow head back to the connector on the seats, I am likely sure the new sending unit comes with one? Can anyone confirm?

On the other note, yep I can start this thing without pressing the clutch, is it just a matter of a new switch then? All seems easy enough

 

 

Ha don't know if that's pointed at me or me trying to sort out the "butchered bird" Hey the rest of the interior is now gutted though and aside from a whole bunch of mouse turd the rest of the wiring inside looks kinda normal and I'll take that as a win! haha