where is fuel pump RELAY on 1996?
02-19-2014, 09:50 PM
#2
My FSM says its behind the lower right side trim panel. I'm pretty sure they mean the lower right side knee panel (lower dash) inside the passenger side. It says you also have to remove the relay module cover to get to it. I found a drawing that shows a group of relays under the dash on that side with a cover that snaps on. It contains the fog lamp relay, the courtesy lamp relay, the horn relay, and the fuel pump relay. You may be able to lay on your back and look up towards the middle near the console side. If you have an FSM its page 8C-29 View C. Page 8C-31 drawing has it listed as item 21.
Last edited by Klyde; 02-19-2014 at 10:10 PM.
02-19-2014, 10:34 PM
#3
Le Mans Master
My FSM says its behind the lower right side trim panel. I'm pretty sure they mean the lower right side knee panel (lower dash) inside the passenger side. It says you also have to remove the relay module cover to get to it. I found a drawing that shows a group of relays under the dash on that side with a cover that snaps on. It contains the fog lamp relay, the courtesy lamp relay, the horn relay, and the fuel pump relay. You may be able to lay on your back and look up towards the middle near the console side. If you have an FSM its page 8C-29 View C. Page 8C-31 drawing has it listed as item 21.
It's a pain to get to with possibility of breaking plastic getting to it.But I got to ask why you want to go there since they almost never go bad.
What is the actual problem that makes you think it's bad
02-19-2014, 11:16 PM
#4
Drifting
Thread Starter
I'll dig into it deeper soon, been a cold freakin' winter, will check for power at harness at fuel cap before digging into relay since it appears to be difficult to access.
Pump does not come on for 2 seconds when key turned to "ON" as it normally would. New Walboro pump from Racetronix.
02-19-2014, 11:30 PM
#5
Le Mans Master
You do have a valid reason to go there. But I would put a voltmeter on the pump wires just to make sure if there is no voltage going to the pump. If no voltage to the pump for the 2 second prime, then I guess the relay is a logical move.
Did you check the pump fuse #14?
Did you check the pump fuse #14?
02-19-2014, 11:59 PM
#6
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The Racetronix fuel pump wiring is reversed.
Swap the fuel pump power and ground wires and it'll fire right up!...
Racetronix sends a generic GM wire harness that is for the early GM vehicles and the power and ground wires are reversed.
.
Swap the fuel pump power and ground wires and it'll fire right up!...
Racetronix sends a generic GM wire harness that is for the early GM vehicles and the power and ground wires are reversed.
.
Last edited by GKK; 02-20-2014 at 12:54 AM.
02-20-2014, 12:38 AM
#7
Le Mans Master
Furthermore, even if the relay was bad, the oil pressure switch would activate the pump once the oil pressure hit 4 psi from cranking. This overrides the relay.
02-20-2014, 07:59 AM
#8
Drifting
Thread Starter
02-20-2014, 08:02 AM
#9
Drifting
Thread Starter
It is possible that the pump just went bad! easy fix, just cost $$
02-21-2014, 11:18 PM
#11
Drifting
Thread Starter
I checked for power to the harness by fuel filler that goes to pump, it DOES have power for 2 seconds when key is turned to run, so my conclusion is the Walbro pump is dead, and will NOT be replaced with the same brand. I'll go with a common "Airtex" available everywhere before I put another Walbro in.
Walbro Fuel pump =
6 months? come on man! The original AC Delco lasted 17 YEARS 
So the relay is not the issue, good thing, based on it's location.
Walbro Fuel pump =
6 months? come on man! The original AC Delco lasted 17 YEARS So the relay is not the issue, good thing, based on it's location.
02-22-2014, 09:25 AM
#12
Le Mans Master
I checked for power to the harness by fuel filler that goes to pump, it DOES have power for 2 seconds when key is turned to run, so my conclusion is the Walbro pump is dead, and will NOT be replaced with the same brand. I'll go with a common "Airtex" available everywhere before I put another Walbro in.
Walbro Fuel pump = 6 months? come on man! The original AC Delco lasted 17 YEARS
So the relay is not the issue, good thing, based on it's location.
Walbro Fuel pump =
6 months? come on man! The original AC Delco lasted 17 YEARS So the relay is not the issue, good thing, based on it's location.
02-22-2014, 11:22 AM
#13
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When my Walbro fuel pump died after 4 months, I posted on Racetronix's Forum as instructed and the owner called me and could not accept blame!...
He kept insisting that my fuel was contaminated or I installed it incorrectly or something!...I said, The fuel and fuel tank are clean, new fuel filter, new Bosch III's and I've installed a fuel pump before which is very simple in a C4 Vette.
I also, told him I had to reverse the power and ground wires. He said, the wire harness included in the 90-96 C4 kit is a Generic GM harness that's made to fit many different years of GM fuel pumps and some need the power and ground wires reversed. So, I said, Then why does the description say, "There are no wires to cut, crimp or splice. All connections are Plug & Play."
He then said, they can't change all the packaging now so, I said, why don't you just insert a note on every C4 Vette order that says, "The Power and Ground wires must be reversed before installation" or, just correct the website description?..... He had an excuse for everything!...Unbelievable!!!
He wanted me to send him the pump so, they can cut it open to see if it was the problem. I said, I know it's the problem because I installed a Delphi pump and the engine runs fine now! He said, the walbro pump uses two gears which have a very tight tolerance and sensitive to contamination which is why it needs the 30 micron fuel sock. Also, I said, I'll cut the pump open myself to see what it looks like before sending it back to you...
I bought from Racetronix because of their "Excellent customer service" but, I found out different.
Sorry, for the Rant...
.
He kept insisting that my fuel was contaminated or I installed it incorrectly or something!...I said, The fuel and fuel tank are clean, new fuel filter, new Bosch III's and I've installed a fuel pump before which is very simple in a C4 Vette.
I also, told him I had to reverse the power and ground wires. He said, the wire harness included in the 90-96 C4 kit is a Generic GM harness that's made to fit many different years of GM fuel pumps and some need the power and ground wires reversed. So, I said, Then why does the description say, "There are no wires to cut, crimp or splice. All connections are Plug & Play."
He then said, they can't change all the packaging now so, I said, why don't you just insert a note on every C4 Vette order that says, "The Power and Ground wires must be reversed before installation" or, just correct the website description?..... He had an excuse for everything!...Unbelievable!!!
He wanted me to send him the pump so, they can cut it open to see if it was the problem. I said, I know it's the problem because I installed a Delphi pump and the engine runs fine now! He said, the walbro pump uses two gears which have a very tight tolerance and sensitive to contamination which is why it needs the 30 micron fuel sock. Also, I said, I'll cut the pump open myself to see what it looks like before sending it back to you...
I bought from Racetronix because of their "Excellent customer service" but, I found out different.
Sorry, for the Rant...
.
Last edited by GKK; 02-23-2014 at 02:43 AM.