fuel pump not running and injectors not opening
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fuel pump not running and injectors not opening
tried firing up my rebuild and my fuel pump is not working w/o being hot wired and my injectors are not opening (checked with an enjine stehoscope) but they did the first time i tried to fire it but my ignition had a bad connections, and once fixed the fuel system stopped working, already tested the resistor pack by the afm with a multimeter and the realy's by the clucth master cyl and under the dash. any ideas?
and i have a single black wire disconnected, it grounds out on the top side of the tranny opposite the slave cyl and is not the oil pressure eylet, any ideas where that goes?
thanks
Dennis
and i have a single black wire disconnected, it grounds out on the top side of the tranny opposite the slave cyl and is not the oil pressure eylet, any ideas where that goes?
thanks
Dennis
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The ENGINE fuse is blown and or the gnd wires for the ECU on top of the rear rotor housing are not bolted down.
That pissant gnd on the transmission goes to a location near the wiper motor.
If the tach needle moves any at all when going to start, then the engine fuse is good and the main relay is good.
You never said what happens when the fuel pump check connector is jumpered and the key is to ON.
That pissant gnd on the transmission goes to a location near the wiper motor.
If the tach needle moves any at all when going to start, then the engine fuse is good and the main relay is good.
You never said what happens when the fuel pump check connector is jumpered and the key is to ON.
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Originally Posted by HAILERS
The ENGINE fuse is blown and or the gnd wires for the ECU on top of the rear rotor housing are not bolted down.
That pissant gnd on the transmission goes to a location near the wiper motor.
If the tach needle moves any at all when going to start, then the engine fuse is good and the main relay is good.
You never said what happens when the fuel pump check connector is jumpered and the key is to ON.
That pissant gnd on the transmission goes to a location near the wiper motor.
If the tach needle moves any at all when going to start, then the engine fuse is good and the main relay is good.
You never said what happens when the fuel pump check connector is jumpered and the key is to ON.
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That means the MainRelay is good and power to both coil assy should also be good.
Jumpering the yellow, two socket fuel pump check connector, with the key to ON, should confirm the fuel pump is good. It should run continuously once the fuel pump check connector is jumpered.
The CAS rotating is what the ECU is looking for to cause spark and fuel pulsation. If you have spark on the Trail coils, as evidenced by the tach bumping a bit during start, then the injectors should also be clicking.
If this is a 86 car, then the solenoid resistor package has to be installed and plugged to the harness. If you had long meter leads, you could pull the plug off the solenoid resistor package and ohm out the wires from there to the small plug on the ECU. You'd see approx 2-3 ohms if ohming from the resistor package to the small plug on the ECU. That's with the resistor package out of the picture.
OR you could leave everything connected up except the small plug on the ECU, and with the key ON, see if there's batt voltage at each of the green wires on the small plug. I mean the injector wires. Like pure green, green/black, green/white, green/red. Pins 3C, 3E, 3F, 3H.
If you've got that go to the LEAD coil assy and pull apart the small, white, two socket plug and see if there is batt voltage on the black/yellow wire. LEAVE the other wire in that plug alone.
If that's good and the pump runs...................it's flooded. Disable the fuel pump and clear the engine by pulling two spark plugs out. Reinstall the plugs and spray for two seconds, starter fluid into the air filter. That's all you need. Then try starting like this a couple of times. Might work. Does for me. Severely flooded engines..........might not work.
Or if you wanted, spray the starter fluid in that one half inch hose that's on the bottom of the n/a intake duct. It's about a foot from the throttle body. Sort of on a swivel.
Sometimes a rebuild is hard to start.
Jumpering the yellow, two socket fuel pump check connector, with the key to ON, should confirm the fuel pump is good. It should run continuously once the fuel pump check connector is jumpered.
The CAS rotating is what the ECU is looking for to cause spark and fuel pulsation. If you have spark on the Trail coils, as evidenced by the tach bumping a bit during start, then the injectors should also be clicking.
If this is a 86 car, then the solenoid resistor package has to be installed and plugged to the harness. If you had long meter leads, you could pull the plug off the solenoid resistor package and ohm out the wires from there to the small plug on the ECU. You'd see approx 2-3 ohms if ohming from the resistor package to the small plug on the ECU. That's with the resistor package out of the picture.
OR you could leave everything connected up except the small plug on the ECU, and with the key ON, see if there's batt voltage at each of the green wires on the small plug. I mean the injector wires. Like pure green, green/black, green/white, green/red. Pins 3C, 3E, 3F, 3H.
If you've got that go to the LEAD coil assy and pull apart the small, white, two socket plug and see if there is batt voltage on the black/yellow wire. LEAVE the other wire in that plug alone.
If that's good and the pump runs...................it's flooded. Disable the fuel pump and clear the engine by pulling two spark plugs out. Reinstall the plugs and spray for two seconds, starter fluid into the air filter. That's all you need. Then try starting like this a couple of times. Might work. Does for me. Severely flooded engines..........might not work.
Or if you wanted, spray the starter fluid in that one half inch hose that's on the bottom of the n/a intake duct. It's about a foot from the throttle body. Sort of on a swivel.
Sometimes a rebuild is hard to start.
Last edited by HAILERS; 03-24-07 at 01:33 PM.
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not stated
car has msd 6a
s5 na mani's
new walbro
most emissions removed
turns out the pump runs per spec, it runs when the car is being turned over, getting spark cause the timing light comes on, and i pulled a plug and checked it that way too
car has msd 6a
s5 na mani's
new walbro
most emissions removed
turns out the pump runs per spec, it runs when the car is being turned over, getting spark cause the timing light comes on, and i pulled a plug and checked it that way too
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might as well change the title of this thread, cause now my injectors are opening and getting fuel, but my meading coils spark once and quit every time i try to turn it over
#10
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Originally Posted by kanuk93gt
how can i check that?
The afm itself has nothing to do with fuel delivery during START.
#11
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^ indeed, but I took this to mean the pump worked during start:
Could be wrong, just throwing that out there.
Originally Posted by kanuk93gt
turns out the pump runs per spec, it runs when the car is being turned over, getting spark cause the timing light comes on, and i pulled a plug and checked it that way too
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