T78 Street Port 3mm... no fuel pressure, help!
#1
T78 Street Port 3mm... no fuel pressure, help!
I recently installed a very nice motor, T78, 3 bar sensor, supra pump, 1680 secondaries and rail, PFC, Datalogit. I've installed 3 singles before, the only difference this time is the T78, 3 bar, and 1680s and secondary rail.
Once I finally got everything installed, I took out the Circuit Opening Relay to starve the motor for fuel so I could prime the motor with some oil pressure. I then put the relay back in to give it some fuel. I turned the igntion to 'on' and the defi fuel pressure gauge (which was untouched through the entire installed) showed 0psi. I tried to crank it anyway and nothing.
I borrowed a Circuit Opening Relay, EGI Relay, and Fuel Pump Relay from another RX-7 to make sure the relays weren't bad. Still no pressure. So I went in and flashed the Power FC again with another map just to change over the secondary injectors and Option 2 for the MAP Sensor and now it won't crank at all. I didn't crank excessively so I don't think that the starter burned out.
Also, on the Sensor screen, the PIM and FUEL were highlighted and maxed out to 5v. Would it be possible for the wires in the 3 bar to be mixed up, causing the 1.82 bar boost to show on the commander and then be cutting the fuel pump?
Any ideas?
Thanks
Richard
Once I finally got everything installed, I took out the Circuit Opening Relay to starve the motor for fuel so I could prime the motor with some oil pressure. I then put the relay back in to give it some fuel. I turned the igntion to 'on' and the defi fuel pressure gauge (which was untouched through the entire installed) showed 0psi. I tried to crank it anyway and nothing.
I borrowed a Circuit Opening Relay, EGI Relay, and Fuel Pump Relay from another RX-7 to make sure the relays weren't bad. Still no pressure. So I went in and flashed the Power FC again with another map just to change over the secondary injectors and Option 2 for the MAP Sensor and now it won't crank at all. I didn't crank excessively so I don't think that the starter burned out.
Also, on the Sensor screen, the PIM and FUEL were highlighted and maxed out to 5v. Would it be possible for the wires in the 3 bar to be mixed up, causing the 1.82 bar boost to show on the commander and then be cutting the fuel pump?
Any ideas?
Thanks
Richard
#2
what fp? how is it wired? do the simple stuff and check for power to the pump, listen for the pump sound on initial key on etc.. the map sensor is wired wrong if it is reading boost with key on. yes that will cause alot of problems. the fuel pump relay just controlls speed not the power, it will allow 12v to bypass the fp resistor when the relay is grounded. car should run without it. by not cranking you mean the engine will not turn over now, or it will not start but the engine turns over?
#4
Tony Stewart Killer.
iTrader: (12)
why would you take out the gm pins from the sensor? Didn't you get the gm connector along with it? The wiring connects like this:
A-grnd-black/grey
B-map sensor volts-green/yellow
C-5V-brown/white
and for the pfc settings put in 41800 for the scale and 0 for the offset.
A-grnd-black/grey
B-map sensor volts-green/yellow
C-5V-brown/white
and for the pfc settings put in 41800 for the scale and 0 for the offset.
#5
I believe I put the pins in the reverse order, I got A and C switched, so my commander is showing 1.82 for boost as ambient. So getting those pins out of the connector is very difficult. I'm hoping this is what caused the fuel pump to cut, but that doesn't sound like the problem after reading mad's post. I think I'm going to take the fuel hose off and see if the pump is pumping... I tried listening for it and don't hear it...
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