Please help me correctly wire my Fuel pump relays - PLEASE!

[twin plugged targa]

Please can someone hlep me re wire my fuel pump relays correctly - or indicate the bad wires.

I am assuming I have an extra (square) relay which may have been for an aftermarket alarm which maybe dissabled the rear fuel pump relay (red relay on far right)

If I interrupt power to the square relay the car will not start, you can hear combustion (firing) whilst turning over but it will not fire once starter motor dissengaged.

Should the car tick over with only 1 (front) fuel pump running?

Should I just remove the connections to the square relay and power the red wire (from the rear relay- far right in pic) direct to a fuse? what amp fuse?

Are there any other wires that should be removed from the rear fuel pump relay harness which are also not standard?

I am trying to remove any wires which may be compounding my electrical unreliability issues.

930 non start issue- continued

Here is what I posted on old threads but has had no replies:
Have found that an aftermarket relay which is in the position normally reserved for the oil cooler relay is hooked into one of the fuel relays?? (930 - has 2 fuel pumps and relays)

This square relay takes power from the fuse strip (yellow fat wires marked) and feeds 12v to the rear fuel pump relay - which also appears to have been messed with- rubber boot cut open for access





This text refers to pics below:
The back side of the relays shows the fat yellow wires again (yellow arrow)which are attached via bullet connectors to the 1st Fuel relay (red wire- red arrow).
The relay has been cut open at the back and there may be aftermarket blue wires here(2)
Can anyone confirm if the wires at the back of the fuel relay are original?
What wires should be going in /out of the fuel relay??

If I pull the power to the after market relay the car dies or will fire initially but stall immediately.
Should I remove this extra (square) relay and power the 1st fuel relay directly off the fuse block (if so, how many amp fuse?)





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I also found PERMANENT 12v supplied to # 14 socket at the 14 pin connector at the engine bay (left side) this is a fat red wire- powered up with ignition off!!
Is this normal?
Or is this just the charging supply from the alternator to the battery?

Any help appreciated

[jbrown]

A relay is a electronic swith. If you disconnet the 2 larger yellow wires at the square relay and put them together you will bypass the relay. The smaller yellow and the black wire are to activate the relay. The black is probably ground, you can just cut it out and the yellow is the power or activation wire for the relay. I replaced my round fuel pump relays with the square ones. I only did it because the original relay plug was wearing out and I have a ton of the square relays and they are alot cheaper than the round ones. Other wize they do the same thing.

[cole930]

TwinPlug:

Pin 14 is always powered because it's directly off the pos. terminal of the battery.

It is actually the heavy red lead that comes from the battery and connects directly the started positive lug. The engine harness, when connected to the engine, has a fat red lead that connects to that same starter lug and therefor supply's 12vdc to various components on the engine and ends up in the 14 pin connector.

Cole

[Shadetree930]

You can read through this thread for some fuel pump wiring information ....

930 Fuel Pump Fuse Overload - The Solution

[twin plugged targa]

Thanks Cole930 - that explains the 12v at the 14 pin connector.

Thanks Shadetree930 - I may do that mod. once I get her running right. My #6 fuse is not being used as someone is powerring the relay via #3 fuse with 25amp fuse.
Side question - why do you have 3 red fuel relays? - what does the 3rd one power? A/C? or oil radiator fan?

- I have found what I think was the original power feed for the rear fuel pump (on the right) - it is in the middle pic and it is a red/white large gauge cable (under the yellow arrow) which is disconnected but leads back to the fuse block with a 25amp fuse! (fuse #3)

I have changed the red cable with the bullet connector and re connected this to the red/white cable (supply voltage) and the car starts and runs fine.

On doing this I discovered a rogue (aftermarket) earth cable near the fuse block which leads back behind the dash see pics below - pics taken from removed oil pressure gauge hole

Yellow arrow points to earth cable


Are these relays normal/standard - what do they control?
Looks like someone just jury rigged a diffrerent relay as it would not fit into the relay block?

What is the relay block /socket with the black wires hooked into where a relay should go? Red Arrow

What are these extra wires on 2nd pic - difficult one!



I am having a side issue with my boost gauge dieing as soon as I turn on main beam headlights and also the gauge illumination dissappears when I go on high beam?
Also the high beam indicator illuminates dimly on low beam and dissappears on high beam

Could this all be relay related?

Looks like someone has spliced an alarm into the car all over the place!

Any light shed on this appreciated
Ben