Can Not Hear Fuel Pump When Trying To Start Car... Car Won't Start...

[thepremier]

I am having an issue with my fuel pump not starting when I am trying to start my car. At first I thought it was just an issue where I didn't have enough gas in my tank, so I walked to the gas station and got $12 in gas, put the gas in the tank, but there was nothing...

The engine just kept cranking, but would not turn over at all. The car did not have any trouble starting up this morning, but for some reason it was not starting this afternoon.

It is definitely the fuel tank because I am not getting a pressure reading on my fuel pressure guage under the hood. The reading is at 0... I checked my fuses, and everything seemed fine, now I am unsure what else could be the problem.

The fuel pump is less than a year old, I purchased the Walbro fuel pump + Hotwire Kit from Racetronix so I am unsure what could be the problem at this point.

Any help would be greatly appreciated.

 

[CS99]

Check the wire harness back by the rear bumber that goes to the fuel pump. See if your getting voltage on the pump side of the connector. You need to check this while the engine is being cranked. If you have 12v then I would say that your pump just took a crap.

 

[Bent6]

Walbros die with no warning sometimes just like what you are describing - work fine then you go to start one day and they are dead. I would verify voltage to the pump but it sounds like it pooped out on you.

 

[KevinB]

Walbros die with no warning sometimes just like what you are describing - work fine then you go to start one day and they are dead. I would verify voltage to the pump but it sounds like it pooped out on you.

I would start by checking the voltage like Bent6 said. If there is voltage, chances are the pump is dead. If no voltage, check all fuses and the relay...basically start from the back of the car and work your way to the front checking for voltage at each connection (ie. before and after the relay, fuse holders, etc.) Also check the pump fuse in the factory fuse box. If the ECM died, the car will still crank, but will not trigger the pump, so check the ecm for power and is functioning correctly.

 

[Sam Colalillo]

I'll try to help, Going off memory here so bare with me.

The connector that goes into the fuel tank sending unit contains three wires. Black is ground. A tan wire with a white tracer is the power wire going directly to the fuel pump do you have power at this location? Remember unless your car is running you are only going to have power for two seconds after the key is turned to the run position. This is because the ECM only allows the pump to run for two seconds when the ignition is turned to the run position. The third wire is a power wire also; it is the one that is connected to the rheostat in your tank, it tells your gauge what fuel level to read depending on how much voltage it is receiving.


Check the fuel pump relay wires. The fuel pump relay is the middle relay on the passenger side fender. One of the wires connected to this relay is a dark green wire with a white tracer, located in pin A1 of the fuel pump relay wire harness socket assembly. When you turn the key to the run position the ECM triggers 12 volts for two seconds to the Dark green wire with a white tracer. In order to check this wire for power you will need some help. Get your test light on this lead and have your assistant turn the key to the run position, it should turn on the test light for two seconds, does it?

If the test light indicates you have power for two seconds then the internal Ecm relay is working. If it does not light then there is a problem with this circuit.

If it lights then turn the ignition key to off and probe the tan with white tracer wire plugged into the fuel pump relay (socket B).

Did it light up for two seconds?

If it did not light up check the black with white tracer, is it making a good ground?

If the ground is good and the tan with white tracer is not powering up you probably have a bad relay.



Hope this makes sense

 

[Rodney87GN]

In addition to what everyone else said...the oil pressure switch or its wiring could be faulty. Remember, it's tied into the fuel pump relay to activate the fuel pump in case of relay failure. It would take about 10 seconds of cranking to build up enough oil pressure to turn on the fuel pump. It does seem like a common problem for the oil psi switch plug to get messed up due to age.

 

[whitecobra98]

In addition to what everyone else said...the oil pressure switch or its wiring could be faulty. Remember, it's tied into the fuel pump relay to activate the fuel pump in case of relay failure. It would take about 10 seconds of cranking to build up enough oil pressure to turn on the fuel pump. It does seem like a common problem for the oil psi switch plug to get messed up due to age.

i second this...it happened to me about three weeks ago..driving down the road, the car just shut off....it cranked and cranked but wouldn't start...i turned the key and didnt hear the fuel pump...had it towed to Cotton's, gave Jack a call, told him what happened, and it got fixed....i was leaning towards fuel pump or relay, but remembered I saw the oil light flash briefly the day before, but my gauge read 70 psi so I didnt think anything of it....oil pressure switch ground went bad....good luck

 

[GN Bob]

One more connection to check that I found to be my problem is the fuel pump prime pin on the ECM connector.

Mine was oxidized so bad from water dripping on it I had to pull the pins from the connector to clean them. You can get the pinout from GNTTYPE.org. Use contact cleaner to clean the pins and connector. Plug in and unplug a few times while they are still wet with cleaner then air dry & coat with a little dielectric grease.

That worked for me.

Good Luck.

Bob

 

[b_rich24]

The connector that goes into the fuel tank sending unit contains three wires. Black is ground. A tan wire with a white tracer is the power wire going directly to the fuel pump do you have power at this location? Remember unless your car is running you are only going to have power for two seconds after the key is turned to the run position. This is because the ECM only allows the pump to run for two seconds when the ignition is turned to the run position. The third wire is a power wire also; it is the one that is connected to the rheostat in your tank, it tells your gauge what fuel level to read depending on how much voltage it is receiving.


Check the fuel pump relay wires. The fuel pump relay is the middle relay on the passenger side fender. One of the wires connected to this relay is a dark green wire with a white tracer, located in pin A1 of the fuel pump relay wire harness socket assembly. When you turn the key to the run position the ECM triggers 12 volts for two seconds to the Dark green wire with a white tracer. In order to check this wire for power you will need some help. Get your test light on this lead and have your assistant turn the key to the run position, it should turn on the test light for two seconds, does it?

If the test light indicates you have power for two seconds then the internal Ecm relay is working. If it does not light then there is a problem with this circuit.

If it lights then turn the ignition key to off and probe the tan with white tracer wire plugged into the fuel pump relay (socket B).

Did it light up for two seconds?

If it did not light up check the black with white tracer, is it making a good ground?

If the ground is good and the tan with white tracer is not powering up you probably have a bad relay.

If you haven't yet - check your ground first, then your relays. After verifying both are good, then I'd follow this post. I hate to hear of people removing/replacing things before checking the simple stuff.

Been there - done that.

 

[HeatleyRacing]

When I bought my GN several weeks ago, I ran into this same problem.. Seems there was HIDDEN mini kill switch that was close to a regular access area that was accidentally flipped. Took me HOURS of troubleshooting to figure it out. Car cranked fine , the switch just killed power to the fuel pump..

 

[Sam Colalillo]

In addition to what everyone else said...the oil pressure switch or its wiring could be faulty. Remember, it's tied into the fuel pump relay to activate the fuel pump in case of relay failure. It would take about 10 seconds of cranking to build up enough oil pressure to turn on the fuel pump. It does seem like a common problem for the oil psi switch plug to get messed up due to age.

HUh?
I don't think this is true. The oil pressure switch is a back up to the relay. Should the relay go bad while your driving down the road, the oil pressure switch will keep the circuit open so the ca will stay running. It is a fail safe for the relay, I don't think it will shut the fuel pump down.

 

["Turbo-T"]

Walbros die with no warning sometimes just like what you are describing - work fine then you go to start one day and they are dead.

That's scary. Is it all Walbros or just some? What's the fix?

 

[Rodney87GN]

HUh?
I don't think this is true. The oil pressure switch is a back up to the relay. Should the relay go bad while your driving down the road, the oil pressure switch will keep the circuit open so the ca will stay running. It is a fail safe for the relay, I don't think it will shut the fuel pump down.

Yes you are right...I should have said that if one of the wires to the oil psi switch was grounding out then it would probably blow the fp/inj fuse...which would cause the fuel pump to not run. Didn't mean to imply that a bad oil psi switch would not cause the car to start, though it does sound like it!

Sorry for the confusion!