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I am installing a New Vintage dash in my 87 irocz. I got all the required wires connected to the new master gauges (tach and speedo) and looks like everything works but now it seems the fuel pump somehow is not getting power, no prime and won't start. What wires in the dash harness could cause this to happen. The only thing I have not used from original dash wires is the brown wires (one says voltage indicator and one says buffer signal). Attached photos are instructions and original dash pinout
This is for a 1987 Camaro?
Which Engine came in the Vehicle originally (or give me the 8TH digit of the VIN, if you do not know about the original Engine)?
Does the Oil Pressure Instrument operate?
Have you tried powering the Electric Fuel Pump from the ALDL Connector (Terminal G with 12V+) ?
Or jumping-out the Electric Fuel-Pump Relay, that the ALDL Connector goes to?
305 tpi original engine
I did not try jumping out the relay, but it is a brand new relay
Thank you for telling me that the car was built as a 305-TPI.
However, this would go faster if you answered all my questions.
In regard to jumping the Relay...
You are testing to see if the Electric Fuel Pump will operate by removing Three potential causes:
-1: the Relay is faulty.
-2: the positive Trigger is faulty: 12V+ from the PCM, when the Ignition-Switch is ON.
-3: the negative Trigger is faulty: Ground connection.
Last edited by vorteciroc; Sep 8, 2021 at 01:46 AM.
I jumped out the relay and pump did not come on.
There had been no issues with the fuel pump until I took out the dash and wired the New Vintage dash.
my question is
"what is in the dash wiring that would cause the pump to not come on that I possibly have wired wrong?"
I cannot figure it out.
Everything was working as it should, fuel pump is brand new (7 months ago and car hasn't been driven, trying to finish interior)
Car has been garage kept not much as far as corrosion, never been any wiring issues.
It was working completely normal and only thing I did was unplug stock dash and wire in new dash.
Which wires in gauge cluster would cause pump to not get power?
Here is the Electric Fuel-Pump Schematic for your exact Car (Year and Engine):
None of the involved Wiring goes to the Instrument-Panel.
Only one Leg of the Circuit goes through the Dash-Board.
-The Tan with White-Tracer Wire comes into the Passenger-Compartment through the Passenger-Side Fender (from the Engine-Compartment).
-It goes into the C207 Electrical-Connector on the Passenger-Side of the Dash-Board.
-Comes Out of C207 as a Brown Wire and goes all the way across the Dash-Board, and into the C208 Electrical-Connector on the Driver-Side.
-Comes Out of C208 as a Tan Wire and travels under the Interior-Trim along the Driver-Side Sill-Plate.
-From there it essentially goes under and around the Back-Seats to the Pass-Through C313 Electrical-Connector, and into the Fuel-Tank.
The Only locations under the Dash-Board, that you could have interacted with are the C207 and C208 connections.
Otherwise there would be signs of other Circuits not operating.
If everything that you have Posted is accurate...
I really suspect that the Electric Fuel-Pump is not Grounded properly or dead.
New Components die all the time...
With all of the Parts that I come across, as a Business...
I see plenty of bad Parts; even Parts that were bad in the Package (never used).
The Electric Fuel-Pump Relay is illustratedINCORRECTLY (the Image in my Post above) in the 1987, 1988, and 1989 GM Service-Manuals (possibly others as well).
The 1992 Schematic below does have the Electric Fuel-Pump Relay illustrated CORRECTLY.
-Terminal E of the Relay is Power-OUT to the Pump.
-Terminal C of the Relay, is the "Normally-Closed" Power-IN to the Relay from the ALDL Connector.
(If Relay is OFF, Power can be put into the ALDL to Test-Run the Pump).
-Terminal A of the Relay, is the "Normally-Open" Power-IN to the Relay from Battery-Power/ Fuse #2.
(If Relay is ON, the Pump will Run).
-Terminal D is the 12V+ Trigger from the PCM.
-Terminal B is the Ground Trigger.
Last edited by vorteciroc; Oct 1, 2021 at 06:40 PM.
It seems the first diagram is a little more accurate to my car as it has the mass air flow circuit/relay in it.
where is the fuel pump switch located (the one the diagram shows that has one orange wire going into it and a tan/white coming out.
The FP switch, and mass air relay, and two other tan/white wires have the tan/white wire that go into "s145" . What/where is that?
Right now I have the brown wire in dash that says "buffer signal" (see original post with dashboard wire labels) just capped because i had to use a speed sensor in place of the mechanical one which has a white signal wire that goes to the new gauges. Should the brown buffer signal need to go somewhere?
thanks for the help
It seems the first diagram is a little more accurate to my car as it has the mass air flow circuit/relay in it.
where is the fuel pump switch located (the one the diagram shows that has one orange wire going into it and a tan/white coming out.
The FP switch, and mass air relay, and two other tan/white wires have the tan/white wire that go into "s145" . What/where is that?
Right now I have the brown wire in dash that says "buffer signal" (see original post with dashboard wire labels) just capped because i had to use a speed sensor in place of the mechanical one which has a white signal wire that goes to the new gauges. Should the brown buffer signal need to go somewhere?
thanks for the help
Okay, the Colored Image that I posted is the exact schematic for your Car.
However the BLUE-BOX that is labeled as the Fuel-Pump Relay is drawn incorrectly... Only what is inside the BLUE-BOX is wrong.
The Black and White Image is not for your car at all.
However the BLUE-BOX that is labeled as the Fuel-Pump Relay is drawn correctly... and should be substituted for the BLUE-BOX in the Colored Image.
The Fuel-Pump Switch is under the Hood on the Engine and operates if the Engine is producing Oil-Pressure (Nothing to do with the Dash-Board Wiring).
Splice S145 is also under the Hood (Nothing to do with the Dash-Board Wiring).
The Speedometer Buffer has nothing to do with this Thread.
The VSS/ Speedo Buffer/ Brown Wire at the Instrument Panel Cluster, splits in 2.
One Wire goes to the Cruse-Control Module in the Dash-Board.
The Other goes through the C207 Connector and to the PCM.
Ok, one of my earlier posts was incorrect . I have 12v at the orange wire at relay and when I jumped that to the tan/white wire fuel pump does come on , I hadn't heard it before.
attached is a picture of the new relay and the plug going into it. Does this look accurate?
Update:
I feel very stupid right about now. All this trouble shooting for no reason . I'm sitting in car and happen to look over and I failed to reconnect the ecm! Fired right up
I'm sorry for wasting your guys time. However I do appreciate all the help and was not all for nothing. I now have a much better understanding of the wiring system, learning something new is never a bad thing.
thanks again!
