fuel pump problems....
#1
fuel pump problems....
i have tried jumping the tester in the engine compartment, and the fuel pump wont run.
so i tried running a wire from the battery to the blue wire coming off of the fuel pump and the emergency 4ways started blinking and the logicon started buzzing
so i tried running a wire from the battery to the blue wire coming off of the fuel pump and the emergency 4ways started blinking and the logicon started buzzing
#3
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On a series four, the fuel pump has a pigtail harness that connects to the Rear harness. The fuel pump wire in the Rear harness is Blue. It mates with a black/white wire in the fuel pump pigtail harness.
#4
yeah i found that out. i am going to hardwire the pump today but what would cause it to not turn on when i turn the key on? everything worked fine before i pulled the engine/trans and harness out of my old car...and i would hate to have to rig stuff when i could just be overlooking something.
#5
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The yellow two pin fuel pump check connector has two wires. One wire goes to a ground point on the engine. The same ground point for the ECU grounds. Located on a series four engine, on top of the rear rotor housing.
The other wire in that connector goes to the Circuit Opening Relays coil. So what happens when you jumper it, is your putting a ground on the wire that goes to the Circuit Opening Relay to pull it in and make the fuel pump work.
So try this. Put a piece of wire to ground on one end of that new wire. Then put the other end of that new wire to the top socket in the yellow two pin fuel pump check connector. IF the key is to ON, the pump should run. The *top socket* would be the one that forms the top of the "tee". The brown wire.
The 10mm wrench size bolt that holds the boost/pressure sensor on the chassis is a good ground point fyi.
IF the pump now runs, I'd start wondering if the grounds for the ECU are in place or...not.
Fuel pumps should not run unless the key is On and the fuel pump check connector is jumpered. Or if the key is On and the vane in the afm is pushed aft at least a 1/8". Key just to ON should not make the pump work.
The other wire in that connector goes to the Circuit Opening Relays coil. So what happens when you jumper it, is your putting a ground on the wire that goes to the Circuit Opening Relay to pull it in and make the fuel pump work.
So try this. Put a piece of wire to ground on one end of that new wire. Then put the other end of that new wire to the top socket in the yellow two pin fuel pump check connector. IF the key is to ON, the pump should run. The *top socket* would be the one that forms the top of the "tee". The brown wire.
The 10mm wrench size bolt that holds the boost/pressure sensor on the chassis is a good ground point fyi.
IF the pump now runs, I'd start wondering if the grounds for the ECU are in place or...not.
Fuel pumps should not run unless the key is On and the fuel pump check connector is jumpered. Or if the key is On and the vane in the afm is pushed aft at least a 1/8". Key just to ON should not make the pump work.
#7
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No. I'm saying the top slot (should be a brown wire).
Jumper a ground to the top slot.
Not from the lower slot to the top, but a piece of wire with one end going to ground somewhere, and then the other end of that wire into the top slot where the brown wire is.
As in: get a piece of wire. Bare both ends. Wrap one end of that wire around the threads of the bolt that holds the pressure sensor on the chassis. Then put the other end of that wire into the top slot of the yellow two socket check connector. Key to ON. Pump should run. IF it does not, then there is a problem somewhere other than what I suggested.
If you ground the Brown wire, the circuit opening relay will pull in and feed the fuel pump. Ignore the bottom wire which should be a Black wire. Ignore it because the pump didn't come on when you tried earlier, so I assume that black wire isn't really going to ground like it should.
IF you have a meter, put it on ohms and see if that black wire is actually going to ground. Should show 1-4 ohms if it is grounded.
Jumper a ground to the top slot.
Not from the lower slot to the top, but a piece of wire with one end going to ground somewhere, and then the other end of that wire into the top slot where the brown wire is.
As in: get a piece of wire. Bare both ends. Wrap one end of that wire around the threads of the bolt that holds the pressure sensor on the chassis. Then put the other end of that wire into the top slot of the yellow two socket check connector. Key to ON. Pump should run. IF it does not, then there is a problem somewhere other than what I suggested.
If you ground the Brown wire, the circuit opening relay will pull in and feed the fuel pump. Ignore the bottom wire which should be a Black wire. Ignore it because the pump didn't come on when you tried earlier, so I assume that black wire isn't really going to ground like it should.
IF you have a meter, put it on ohms and see if that black wire is actually going to ground. Should show 1-4 ohms if it is grounded.
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#8
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Listen carefully when you jumper the yellow connector with the key ALREADY to ON. Do you hear a click when you jumper the connector? You should hear the circuit opening relay pull in and *click*. Also, make sure the ENGINE fuse is good. It is what feeds the circuit opening relay and in turn the fuel pump.
Another way to make the pump come on: remove the small wire from the starter solenoid. Just pull it off so the starter won't turn over. Then HOLD the key to START. The pump should run as long as the KEY is HELD to START. If it does not, then make sure the ENGINE fuse is good.
#10
Listen carefully when you jumper the yellow connector with the key ALREADY to ON. Do you hear a click when you jumper the connector? You should hear the circuit opening relay pull in and *click*. Also, make sure the ENGINE fuse is good. It is what feeds the circuit opening relay and in turn the fuel pump.
Another way to make the pump come on: remove the small wire from the starter solenoid. Just pull it off so the starter won't turn over. Then HOLD the key to START. The pump should run as long as the KEY is HELD to START. If it does not, then make sure the ENGINE fuse is good.
Another way to make the pump come on: remove the small wire from the starter solenoid. Just pull it off so the starter won't turn over. Then HOLD the key to START. The pump should run as long as the KEY is HELD to START. If it does not, then make sure the ENGINE fuse is good.
#12
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So since it clicks, maybe take a meter and see if there's batt power on the Blue wire of the fuel pump connector.
This a turbo or non turbo car???? Might make a difference. What year?????
#14
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Well, on a TurboII, the circuit opening relay pulls in and sends the fuel pump power to the FUEL PUMP AND RESISTOR package. That package is located just in front of the air filter assy. It has fins on it. Make sure its plug is connected. The outfit is bolted to the bulkhead the headlights are bolted to.
The power goes from the circuit opening relay.........to the Fuel Pump and Resistor package......leaves the package and goes to the blue wire on the fuel pumps elect plug.
The power goes from the circuit opening relay.........to the Fuel Pump and Resistor package......leaves the package and goes to the blue wire on the fuel pumps elect plug.
#15
okay! that was unplugged now i can hear the pump but it sounds very sluggish...and it is a walbro i can normally hear its high pitched wine. maybe the battery is low i will try and hook it up with jumper cables but what else could it be? sorry for all of the trouble i have to move home to michigan on sunday and need to get this going (pm me your paypal)
#19
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The power for the coils goes as follows: From the EGI INJ fuse.........to the Main Relay.....to the coils.
I more or less know your Main Relay is pulling in because your fuel pump works. The ENGINE fuse powers both main relay and circuit opening relay.
Neither coils nor fuel injectors will work if the ECU ground on top of the rear rotor housing is off. Jpg attached of where that ring terminal is on top of the engine.
CAS has to be plugged in also.
I more or less know your Main Relay is pulling in because your fuel pump works. The ENGINE fuse powers both main relay and circuit opening relay.
Neither coils nor fuel injectors will work if the ECU ground on top of the rear rotor housing is off. Jpg attached of where that ring terminal is on top of the engine.
CAS has to be plugged in also.
#21
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EGI INJ fuse in the engine bay fuse box good? One of the two most inboard fuses.
Good fuses? Then pull the Main Relays large connector apart. No key needed. See if you have batt power on two of the four pins. Should be on two of them.
Do you hear the Main relay pull in/click when the key is put to ON?
Are all the harnesses stock? Any changes in the harnesses from what they originally were?
Good fuses? Then pull the Main Relays large connector apart. No key needed. See if you have batt power on two of the four pins. Should be on two of them.
Do you hear the Main relay pull in/click when the key is put to ON?
Are all the harnesses stock? Any changes in the harnesses from what they originally were?
#22
EGI INJ fuse in the engine bay fuse box good? One of the two most inboard fuses.
Good fuses? Then pull the Main Relays large connector apart. No key needed. See if you have batt power on two of the four pins. Should be on two of them.
Do you hear the Main relay pull in/click when the key is put to ON?
Are all the harnesses stock? Any changes in the harnesses from what they originally were?
Good fuses? Then pull the Main Relays large connector apart. No key needed. See if you have batt power on two of the four pins. Should be on two of them.
Do you hear the Main relay pull in/click when the key is put to ON?
Are all the harnesses stock? Any changes in the harnesses from what they originally were?
all fuses look good. harness is stock
all i hear clicking is the white connector to a yellow plug with black cap under the dash, where a fuel cut switch used to be spliced
#23
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Sounds like the Main Relay isn't pulling in for some reason. The ENGINE fuse powers it and the circuit opening relay so it's not that fuse.
The Main Relay gets it's ground from a gang of ground wires attached to the back of the left strut tower. The Trail Coil has to be removed to see them. There's maybe four-six black wires in a plug that plug into a metal outfit bolted to the back of the strut tower.
Here's what you might do if you have no meter nor anybody handy. Pull the positive cable off the battery. Then go turn the key to ON. Now go back and put the positive cable back on the battery. Listed for the main relay pulling in/clicking. It's located just aft of the Trail Coil assy. It's ususlly held on the fender with one phillips type screw. Large metal relay. Colored ?? **** stained looking on some cars.