Wiring Harness ?'s Need help bad..

Dark_5.0 · 11-03-2003, 09:34 AM

Ok picture this in your head. On an 87 coupe on the drivers side of the engine bay right by the firewall there are to connectors that go to the dash harness a black one and a gray one.

I converted this car over to mass air and on the harness I used there are not two connectors to plug to the dash harness there is only one and it is a brownish red color. I plugged it into the gray connector just to see if it would work without the black one plugged in Everything works except the fuel pump. So I am assuming the black connector goes to the fuel pump.

How do I hot wire the fuel pump so that it operates normally?

Please...I need help bad.

crazypete · 11-03-2003, 10:23 AM

ok, there is in the ECU testing harness, a wire that runs to the fuel pump that if you ground, the FP will run. The third one on the long row is for the + connection and the one on the top row opposite side is for the returning signal from the eec-iv. So it is the remaining one (sorry, I tossed my eec-iv a long time ago for a carb). Now wire this so a relay opens to ground when you key on. WARNING: this will build pressure in the system so never just key-on. You have to key on and start! Yes, this is a "hack" but it will get your car running!

Dark_5.0 · 11-05-2003, 05:57 PM

I ended up cutting the connectors off and I started splicing wires. It took about 3 hours to figure everything out but I got it.

Damn Im good

QuantumMotorsports · 11-07-2003, 10:47 AM

Crazypete, if your fuel pump runs continuously with the engine off, it's not going to continuously build pressure. That's what the pressure regulator is for. It has a fuel return to the gas tank and once the pressure reaches 40 lbs or whatever the no vacuum regulated pressure is set at, it simply starts pumping fuel from the tank through the regulator back to the tank.

crazypete · 11-07-2003, 12:44 PM

I've actually sat and watched it when I set up my carb and I was still messing with trying to regulate the high pressure pump into a low pressure carb. This is with DUAL FPR's (a malloy 3 port with return line and a holley 2 port afterward with a guage right before the lines split for the fuel bowls). When I went key on, the prssure would go to the 7psi I set and then start rising sloooowly but surely until it hit 15psi and I would shut if off.

I know, I'm comparing apples to oranges, but the EEC cuts off the fuel flow for a reason after key-on no start I'm sure.

11-03-2003, 09:34 AM	#1
Dark_5.0 Registered Member Join Date: Apr 2001 Location: Staging lane Posts: 4,337	Wiring Harness ?'s Need help bad.. Ok picture this in your head. On an 87 coupe on the drivers side of the engine bay right by the firewall there are to connectors that go to the dash harness a black one and a gray one. I converted this car over to mass air and on the harness I used there are not two connectors to plug to the dash harness there is only one and it is a brownish red color. I plugged it into the gray connector just to see if it would work without the black one plugged in Everything works except the fuel pump. So I am assuming the black connector goes to the fuel pump. How do I hot wire the fuel pump so that it operates normally? Please...I need help bad. __________________ 92' LX-Big brakes, Lots and lots of suspension, GT40X heads, Ported cobra intake, stock cam, Vortech SC trim. 00' Lightning-Stock 88'CRX-13 second ego killer

11-03-2003, 10:23 AM	#2
crazypete Registered Member Join Date: Sep 2002 Location: Boston Posts: 592	ok, there is in the ECU testing harness, a wire that runs to the fuel pump that if you ground, the FP will run. The third one on the long row is for the + connection and the one on the top row opposite side is for the returning signal from the eec-iv. So it is the remaining one (sorry, I tossed my eec-iv a long time ago for a carb). Now wire this so a relay opens to ground when you key on. WARNING: this will build pressure in the system so never just key-on. You have to key on and start! Yes, this is a "hack" but it will get your car running! __________________ 91 GT Carb conversion, holley 600 double pumper, edelbrock performer intake, FMS "C" drop springs, march 1000 underdrive pullies, crane 1.7 roller rockers, GT-40P headers, bassani x pipe, american thunder catback, FMS 4.56's, msd aL6, trunkmount battery, A/C eliminator kit, 3000 stall tci streetfighter, AOD with transgo kit, A+ servo, 300M hardened lockup shaft, kevlar bands and 28,000 gvw trans cooler, 3 core radiator, 300 lbs stripped with a full interior

11-05-2003, 05:57 PM	#3
Dark_5.0 Registered Member Join Date: Apr 2001 Location: Staging lane Posts: 4,337	I ended up cutting the connectors off and I started splicing wires. It took about 3 hours to figure everything out but I got it. Damn Im good __________________ 92' LX-Big brakes, Lots and lots of suspension, GT40X heads, Ported cobra intake, stock cam, Vortech SC trim. 00' Lightning-Stock 88'CRX-13 second ego killer

11-07-2003, 10:47 AM	#4
QuantumMotorsports Registered Member Join Date: Jul 2000 Location: Norman, Oklahoma, USA Posts: 597	Crazypete, if your fuel pump runs continuously with the engine off, it's not going to continuously build pressure. That's what the pressure regulator is for. It has a fuel return to the gas tank and once the pressure reaches 40 lbs or whatever the no vacuum regulated pressure is set at, it simply starts pumping fuel from the tank through the regulator back to the tank. __________________ Michael Black QuantumMotorsports Norman, OK 1984 LX Hatch 306 w/ TRW forged flat toppers, Comp Cams Magnum 292H, GT40P heads w/ 3 angle valve job, .550 lift springs, Angus Racing Roller Rockers, Weiand Stealth Intake, Holley 4150 650cfm carb, MAC 1 5/8 Long Tubes, Single Chamber Flowmasters, 91' T5 w/ Pro 5.0 shifter, Turbo Coupe 8.8 Rear w/ 3.55 gears, QA1 Motorsports tubular K member, no interior except steering wheel and seat. Coming soon: 6 or 8 point cage, Fuel Cell, Weld Draglites

11-07-2003, 12:44 PM	#5
crazypete Registered Member Join Date: Sep 2002 Location: Boston Posts: 592	I've actually sat and watched it when I set up my carb and I was still messing with trying to regulate the high pressure pump into a low pressure carb. This is with DUAL FPR's (a malloy 3 port with return line and a holley 2 port afterward with a guage right before the lines split for the fuel bowls). When I went key on, the prssure would go to the 7psi I set and then start rising sloooowly but surely until it hit 15psi and I would shut if off. I know, I'm comparing apples to oranges, but the EEC cuts off the fuel flow for a reason after key-on no start I'm sure. __________________ 91 GT Carb conversion, holley 600 double pumper, edelbrock performer intake, FMS "C" drop springs, march 1000 underdrive pullies, crane 1.7 roller rockers, GT-40P headers, bassani x pipe, american thunder catback, FMS 4.56's, msd aL6, trunkmount battery, A/C eliminator kit, 3000 stall tci streetfighter, AOD with transgo kit, A+ servo, 300M hardened lockup shaft, kevlar bands and 28,000 gvw trans cooler, 3 core radiator, 300 lbs stripped with a full interior

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