Help....Is my fuel pump shot????
Thread Starter
Burning Brakes
Joined: Nov 2004
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From: Grafton Ohio
Help....Is my fuel pump shot????
Since it was such a nice day here in northern Ohio I decided to take the car out for a short drive. I hopped in and she fired right up but sounded a little rough. I gave it some gas a few times and it definately had a misfire. Upon returning to idle it died and would not refire. I pulled a few plugs and they didnt look bad but since I've run into spark plug issues before I put my spares in. Still no start. I fully charged my battery and cleaned my front chassis grounds, still nothing. So on a whim I plugged in my f/p gauge on the fuel rail and nothing! My pump relay is ok and you can hear the pump whine for a few seconds when you turn the key. I pulled the filter to see if it was clogged and it's fine. I hooked everything back up pulled my supply line from the fuel rail and pressurized my tank and I get fuel so no clogged lines. This fuel pump is not even a year old. It's an LPE in tank pump. I've never had this kind of problem before. Is there anything else I can diagnose before pulling the pump or am I once again destined for a 94 octane shower. Thanks in advance for any help you all can give. Jeremy
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Jeremy
I need to figure out is you have fuel pressure or not! You made this statement "My pump relay is ok and you can hear the pump whine for a few seconds when you turn the key." If the pump makes noise, you may very well have fuel pressure and may have an injector issue!
See if you can figure out if you have fuel pressure and if you can't read the pressure, just hit the schreded valve pin with a small screwdriver and see if you can get fuel to squirt out!
After I figure out if you have pressure, we can troubleshoot from there.
Bill C
I need to figure out is you have fuel pressure or not! You made this statement "My pump relay is ok and you can hear the pump whine for a few seconds when you turn the key." If the pump makes noise, you may very well have fuel pressure and may have an injector issue!
See if you can figure out if you have fuel pressure and if you can't read the pressure, just hit the schreded valve pin with a small screwdriver and see if you can get fuel to squirt out!
After I figure out if you have pressure, we can troubleshoot from there.
Bill C
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 822
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From: Grafton Ohio
I also disconnected the supply line from the fuel rail and turned on the key. Nothing.
Then when I pulled my filter for inspection I turned on the key with the filter off thinking I would get a ton of fuel from the line and I got nothing.
The thing that has me confused is that you can hear the pump cycle when you turn on the ign.but get no fuel flow at all.
Then when I pulled my filter for inspection I turned on the key with the filter off thinking I would get a ton of fuel from the line and I got nothing.
The thing that has me confused is that you can hear the pump cycle when you turn on the ign.but get no fuel flow at all.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Just for the hell of it, clean the grounds that are located behind the rear wheels. On your 98 there will be two. One on the drivers side and one on the passengers side. The one on the drivers side is the fuel system ground. They both should be cleaned and are subject to all kinds of severe conditions (Salt, mud water ect...)
Here is a picture of mine. I had to replace the stud with a self tapping metal screw because the stud wrung off. Mine was so corroded that it was intermittant and caused fuel system issues.
You could have just enough connection to allow the pump to run for a short period of time.
It as shot in the dark but it may be a bulls eye!
Here is a picture of mine. I had to replace the stud with a self tapping metal screw because the stud wrung off. Mine was so corroded that it was intermittant and caused fuel system issues.
You could have just enough connection to allow the pump to run for a short period of time.
It as shot in the dark but it may be a bulls eye!
Safety Car
Joined: Jun 2003
Posts: 4,640
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From: Sunshine State
Originally Posted by jers98vet
I also disconnected the supply line from the fuel rail and turned on the key. Nothing.
Then when I pulled my filter for inspection I turned on the key with the filter off thinking I would get a ton of fuel from the line and I got nothing.
The thing that has me confused is that you can hear the pump cycle when you turn on the ign.but get no fuel flow at all.
Then when I pulled my filter for inspection I turned on the key with the filter off thinking I would get a ton of fuel from the line and I got nothing.
The thing that has me confused is that you can hear the pump cycle when you turn on the ign.but get no fuel flow at all.
Bob
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Thread Starter
Burning Brakes
Joined: Nov 2004
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From: Grafton Ohio
Ok The rear chassis grounds have been cleaned and I still get nothing. Does anyone know how to pull a tank? What holds them from the topside and can I fully remove the tank without too many problems. When I replaced the pump last year I left the tank in the car and I got pretty wet with gas. I'm just trying to be a little neater this time. I can put my old pump back in it to see if that is the problem before I go spending more $$$ on another pump. Keep those ideas rolling. Thanks to all responses so far.
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
There is a circuit that controls the pump. The pump just doesnt have a relay and run when the key is on. I am in the process of figuring out how the system works. As soon as I get another brain storm I will let you know.
Bill
Bill
Thread Starter
Burning Brakes
Joined: Nov 2004
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From: Grafton Ohio
Thank you, Bill. I dont know how much longer I'll be on so if you come up with anything at some odd hour of the night, pm or email me. Thanks a bunch! I'm really not looking forward to pulling that pump again.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The PCM controls the fuel pump relay. Before you do too much replacing, I would see if I could jumper the fuel pump relay to apply power to the pump and make it run. While it is in constant run see if you have pressure and see if the car will run.
That will show you one of two things:
The relay is BAD or the PCM/PCM fuel circuit driver is defective.
Bill
That will show you one of two things:
The relay is BAD or the PCM/PCM fuel circuit driver is defective.
Bill
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Is there another relay in the electrical center that has the same part number? If so, I would swap it. You can take the cover off of the relay and manualy press the run contacts together. You can also use a meter and probe the connections inside the relay to make sure that there is 12 VDC on the proper terminals.
Bill
Bill
Thread Starter
Burning Brakes
Joined: Nov 2004
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From: Grafton Ohio
Bill, thanks for the extra input. Do you happen to know what terminals to jump in the fuse block?I dont want to start jumping terminals I'm not sure of and making things any worse. Also I have swapped the horn relay with the f/p relay (same part #s on them) and I still got no f/p but my horn worked with both relays.
Jeremy
Jeremy
Thread Starter
Burning Brakes
Joined: Nov 2004
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From: Grafton Ohio
Ok I ran a jumper wire across the f/p relay to make it run constantly. You can hear the pump whining in the tank but it is not pushing any volume or pressure. I'm going to pull the tank and put my stocker back in it to see if I can get it running. Jeremy
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
That sounds like what you need to do. We have exhausted ALL means of getting pressure. Looks like the connection between the pump and the fuel pipe either came loose or split. The rotor on the pump could have also detached from the motor shaft leaving the motor to work but not pump.
Please repost when you figure out what happened. If you can post some pics of the pump and fuel level assembly that would be GREAT!!
Good job on jumpering out the relay!!
That gave you all of the reasoning that you needed to pull the pump!
Bill C
Please repost when you figure out what happened. If you can post some pics of the pump and fuel level assembly that would be GREAT!!
Good job on jumpering out the relay!!
That gave you all of the reasoning that you needed to pull the pump!
Bill C
Drifting
Joined: Oct 2003
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From: bloomfield nj
are you sure you have fuel in the tanks?the fuel pump will run for 2 seconds with the key on,engine off.once the pcm sees a signal from the crank sensor the pcm will send a ground signal to the fuel pump relay.
i would make sure the tanks have gas first[never rely on the fuel gauge].if the pump sounds sick,you probably have a bad pump,but i would make sure here is fuel in the tanks first.
i would make sure the tanks have gas first[never rely on the fuel gauge].if the pump sounds sick,you probably have a bad pump,but i would make sure here is fuel in the tanks first.
Thread Starter
Burning Brakes
Joined: Nov 2004
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From: Grafton Ohio
Thanks for all the input! Bill's last post was the winner. Upon removing my pump, I was able to pull the plastic flex pipe out of the tank. Once the pump was completly removed, I wired it back up, reconnected the flex pipe to the pump, submersed it in my catch bucket of fuel, turned on the key and it shot fuel everywhere. I replaced the crimp clamp reinstalled everything refilled the tank and it fired right up. Got good f/p atthe rail. Problem solved.
