Jared Garner

Hi everyone, not new to the board exactly, but I haven't had a 3rd Gen in about 8 years and no longer have the e-mail address for my old profile. This past Saturday I picked up a running '87 GTA with the L98 TPI. Haven't had the chance to check the fuel pressure or ohm out the injectors, but I did do the plugs, wires, cap and button today. Runs a lot better, but still needs the timing tweaked a little and has a slight stumble.
My issue.. The fuel pump is jumpered from one of the wires on the relay under-hood to the battery. I wired in a switch for it yesterday for the time being. The cooling fan is also jumpered over to the battery. I read a thread earlier today while researching about the inline fuse from the battery, but uh.. Needless to say, PO wasn't much of an electrician or mechanic (half the plug wires were wrong on the cap.) Can anyone provide me with any tips and/or pics of your wiring at the battery? I'd really like to get the electrical under the hood sorted before I end up with a mess, or a crispy shell.
More info on the car: '87 GTA 5.7 TPI, Flame Red Metallic, Camel Cloth, Gold GTA wheels, Hardtop, Digital dash, 187,xxx miles. Currently yard-drives, but has 3 severely dry-rotted tires and needs the brakes bled.
TIA

B4C5.7

iTrader: (2)

Welcome back Jared, your GTA looks to be rustfree. Nice find!

tealman92

Nice find. Sounds like your relays are bad or fuses. I would test light to see if you have power into all your relays. If not then check all fuses. If yes then replace the relays

Jared Garner

Thanks for the re-welcome! Yes, it's fairly rust-free as far as I can tell, with the exception of the battery tray. Haven't pulled the carpet yet, but the underside altogether is entirely rust-free. All the body panels are original (still has correct VIN stickers on the inside of the 1/4s, etc.,..) I tinkered with the wiring at the battery earlier this evening and spliced a few connections back together, and tied the jumper wire that was powering the fuel pump at the (seemingly wrong) relay [will attach picture of relays] into the weatherpack fuse or whatever it's called coming off the battery. I haven't messed with a TPI system since back in '07 I believe when I had my '86 WS.6, so I'm kinda starting over with it all. I'll have to pick up a test light and digital tester tomorrow so I can test the relays and check the resistance on the injectors as well. If they're bad, I'm looking at:
https://secure.fuelinjectorconnectio...vette-tpi.html
I think those should work? Car seems to run fairly well, aside from some stumbling, but I haven't put any fresh gas in it yet, and have no idea when the PO put gas in it (fella didn't speak English very well, sooo..) It does seem to run smoother over about 2500RPM..
Is there a wiring diagram available that shows which wires to test for +12v? I checked the fuses earlier, under the dash at least, and the inline fuse off the battery + was good as well. Also-- After tying in a few wires at the inline (the round fusible link) off the +, I have SES with key on, finally. Started and idled for a few minutes, tied in the fan wires at the link as well, but they kept running after I shut the car off. Can't remember how long they should run after key-off, so I d/c the battery as I had to make a trip to town.
As far as I've seen so far, the FP relay is the 2Orange, 1 black, 1 blue, but you'll see in the picture that the jumper that's been running the fuel pump has multiple other colors. I thought that was one of the MAF relays?
One other thing- I rented a steering wheel puller so I could replace the ignition lock cylinder, but none of the bolts fit, nor did the 5/16 -18 bolts I bought separately. I'm waiting for the local O'Reilly's to re-order their kit as it was rented out about 2 months ago and never returned.

Jared Garner

Update:
Got most of the other issues resolved. Just need to ohm out the injectors, although I'm pretty sure some/most/all are bad, judging by the waterfall sounds it was making before with the fuel pump jumpered to run. So it looks like the next order of business is acquiring a set of Bosch d3's from SouthBay

Jared Garner

Ohm'd the injectors just now. 16.8 across even numbered injectors, #1=16.7; #3=3.4; #5-7=16.8