I’m having this same problem I have spark no fuel. My pump relay went out so I hard wired the pump to turn on. But do the injectors run off of it for some reason I have a constant ground with key on idk what to do at this point
I don't know if the injectors power passes through the fuel pump relay.
But I would say no due to the fact that the factory workshop manual say to pull the fuel pump relay and turn the engine over to drain fuel pressure.
Are you sure the relay is bad?
There is a yellow two prong plug next to the drivers strut tower, it is beside a single prong green plug, if you jump the two sides of the yellow connector (connect one to the other) the fuel pump comes on without the engine running.
The green plug is the test connector, ground it to the frame and you can pull the engine codes with the check engine light in the cluster.
How many pins are on the relay?
Relays are actually quite simple.
-They use 12v positive and Ground signals to pass (Normally opened) or turn off (Normally closed) a current, it can be negative or positive.
IN current 12V+-> Relay ----->OUT current 12V+
Signal in 12+---->_____<----Signal in Ground
The above relay would be passing a 12V+ current (IN-OUT)
It would be normally opened (needs 12v+ and ground signal to pass current)
Only one signal needs to be switched, the other signal and supply (in) current would be constant.
So if the above N.O. relay was for the headlights, 12V+ leaves the battery, passes through a fuse and goes to the in 12v+ current side of the relay. The ground signal going to the relay is permanent on. The 12V+ signal to activate the relay comes from the headlight switch.
Check the female prongs the relay plugs into using a multimeter.
How many wires run to the fuel pump?
If it's one than + is switched by the relay.
Check the female prongs voltage with the key off for a 12V+ prong ----> current in
Check for a ground signal with the key off ----> ground signal in.
Check for a positive signal with the key on ----> 12+ signal in.
The remaining prong will go to the fuel pump ----> Current out
By a 4pin 40amp 12V Normally Opened universal relay, get some male and female spade connectors.
Take 4 pieces of 18" wire and crimp 1 male and 1 female spade connector one each wire.
Plug the male end into the factory relay socket the relay sat in and the female prong on the universal relay.
The pinout will be:
Relay 30 <----> Current in (Factory socket)
Relay 87 <----> Current out (Factory socket)
Relay 86 <----> 12V+ signal in (Factory socket)
Relay 85 <----> Ground signal in (Factory socket)
Tie wrap the wires so the spade connectors don't come loose and secure the universal relay somewhere out of the way.
To trouble shoot your issue you can jump factory socket current in and current out, bypass the fuel relay and see if the car runs properly.
To add to the info in the dead thread you posted in. The injectors are batch fired 1+3 and 2+4 the ecu activates them, RPM+TPS+VAF+02 signals to the ecu decide the amount they inject but the hall sensors in the distributor dictates when they fire, the other signals have default maps to compensate for failed or bad signals but without the hall sensor signals in the distributor the ecu wont inject fuel or run spark.
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