chopped up wire headed for the fuel pump
Thread Starter
5th Gear
Joined: Jun 2004
Posts: 5
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From: Shapleigh me
chopped up wire headed for the fuel pump
My wife and I recently purchased a 1987 L98 that needs a little fixin' up. We named it the Yebo machine after our best race horse. ( in case anybody was wondering). We took it to have the cruise control and the air conditioner looked at and it Quit in the yard at the garage. The guy was really busy and didn't have time to fix it but He diagnosed the fuel pump. Next day I had the car brought home the wife bought a fuel pump and a chiltons. I talked to friend and he said look for a fuse or a relay. I checked fuses and we found a relay on the firewall that clicked when the switch was turned to on. I checked a plug for spark and had plenty. Well wife had bought fuel pump so I installed it and bench tested old one which seemed to pump. Here we go. Car still won't start. I found a butchered brown wire with white stripe coming from the wire connector to the fuel pump. It is now hooked up to a green wire that goes up the passenger side of car. Right now I am charging the battery overnight. Is this wire suppose to be hot? 3 wires go to the tank, black purple and brown W/ white strip. Any help appreciated. 
Melting Slicks
Joined: Jan 2003
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From: What did the 5 fingers say to the face? SLAP!!
Re: chopped up wire headed for the fuel pump (The YEBO Machine)
My '86 has a tan/white that goes to fuel pump fuse, pink that goes to digital dash, and a black wire (ground). You said you have power at the relay. Do you have power in the FP circuit at the fusebox?
Also check for a fusible link near the battery that has 2 wires in and 2 wires out. One of these wires has a single wire weatherpack connector. On this wire, heading towards the bottom of the car, is a small fusible link. This is the FP feed wire. Make sure you have voltage here.
Also check for a fusible link near the battery that has 2 wires in and 2 wires out. One of these wires has a single wire weatherpack connector. On this wire, heading towards the bottom of the car, is a small fusible link. This is the FP feed wire. Make sure you have voltage here.
Thread Starter
5th Gear
Joined: Jun 2004
Posts: 5
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From: Shapleigh me
Re: chopped up wire headed for the fuel pump (The YEBO Machine)
ok Im past the fuel pump. Now when we turn the key we hear tickticktick from the fuel pump, The car fires up for few seconds. It doen't want anything to do with the gas peddle. It has BOSCH plugs in it, not sure if good or bad. Im thinking (hoping) plugs are loaded up, or (gulp) I Have to squeeze under the darn car to change the fuel filter, I hope not. These cars are not easy to work on if your not set up for them. Chevy garage changed fuel filter about a year ago (said it was severely plugged in service records). I am wondering if it could be plugged again. Inside of gas tank didn't look bad. 
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Re: chopped up wire headed for the fuel pump (The YEBO Machine)
Pick up a fuel pressure gauge at AutoZone (0-60psi), put it on the Schraeder valve on right rear of fuel rail (discharge pressure first), remove and plug the vacuum line the the FPR (just behind the Schraeder), start the engine and take the reading at idle. You should see over 40psi.
Slowly raise idle RPM and monitor fuel pressure; it should not drop significantly. If so change the filter, located in on the right frame just behind a heat shield by the starter. It realy isn't so bad to change though you will likely need to jack the car on that side or put it on ramps.
If fuel pressure holds, open the EST connector in the Tan/Blk wire near the brake booster and check base timing. It should be about 6deg BTDC.
Of course an ignition problem or vacuum leak could also cause such a symptom. I don't think a clogged cat would be that severe just off idle.
Slowly raise idle RPM and monitor fuel pressure; it should not drop significantly. If so change the filter, located in on the right frame just behind a heat shield by the starter. It realy isn't so bad to change though you will likely need to jack the car on that side or put it on ramps.
If fuel pressure holds, open the EST connector in the Tan/Blk wire near the brake booster and check base timing. It should be about 6deg BTDC.
Of course an ignition problem or vacuum leak could also cause such a symptom. I don't think a clogged cat would be that severe just off idle.
Thread Starter
5th Gear
Joined: Jun 2004
Posts: 5
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From: Shapleigh me
Re: chopped up wire headed for the fuel pump (The YEBO Machine)
Finally got the car running. The fuel pump wasn't working because the positive connection was bad in the top of the fuel sending unit. the wire connection looked like it got hot, I took it apart and cleaned it. After I charged battery again overnite it fired right up. Im savoring my sucess for awhile before diving into "WHY IS MY CAR SKIPPING?" lol. 
