Fule pump rele
Thread Starter
Cruising
Joined: Jul 2013
Posts: 13
Likes: 0
From: Ludvika Dalarna
Fule pump rele
Hello I am new to this forum and I live in Sweden. but I've read almost all the Posts and they have helped me to get on with my corvette Projeckt this is the way that I keep on building on a sandy floodet corvette c5 it has rid pretty good has changed all electric parts and started the car. and all the ground is clean. now the fun starts when I turn on igniskon to on sometimes starts fuel pump Rale ticking all the time. and tank gauge goes to low fuel and temp gauge goes to max. and when they are as I have (pcm) non coom. then after her one time when they stop and everything is normal. they are someone here who has been through something similar grateful response /// Karl
Melting Slicks
Joined: Sep 2011
Posts: 2,258
Likes: 544
From: Appleton WI
I cannot help you with your problem but will clarify for others what you are asking.
Karl bought a car that was flooded in Hurricane Sandy. He has done some electrical work and is having a problem with the fuel pump relay. Sometimes when he turns the key on, the fuel pump relay starts ticking, the fuel gage show empty, and the temp gage goes to max. When this happens he has “no communication with the PCM.” (I’m assuming he is pulling the codes) Other times he can start the car and everything is normal.
I’m guessing he might have an ignition switch problem.
Karl – List the codes you are getting and it will help people diagnose your problem.
Hope this helps
Karl bought a car that was flooded in Hurricane Sandy. He has done some electrical work and is having a problem with the fuel pump relay. Sometimes when he turns the key on, the fuel pump relay starts ticking, the fuel gage show empty, and the temp gage goes to max. When this happens he has “no communication with the PCM.” (I’m assuming he is pulling the codes) Other times he can start the car and everything is normal.
I’m guessing he might have an ignition switch problem.
Karl – List the codes you are getting and it will help people diagnose your problem.
Hope this helps
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Verdad Gallardo
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Karl
I have a BIG HEART when people in other countries attempt to work on cars that are this USA COMPLEX!
I will do what I can to assist you with your C5 issues.
The very first place that i would start would be the IGNITION SWITCH.
Here is a post that will allow you to repair your switch. Before you DIG INTO SWITCH REPAIR,,,, use a DC VOLT METER and measure the voltage on the fuel pump fuse to chassis ground. There are TWO TEST POINTS on top of each fuse. Measure eash test point to ground. You should see FULL BATTERY VOLTAGE when the ignition switch is ON.
- C5 ignition Switch repair - http://forums.corvetteforum.com/c5-t...ch-repair.html
If it reads normal, read the test points again when the relay is having it issues. I believe that you are at times UNDER VOLTAGE because the contacts inside the ignition switch are burnt and pitted.
The GROUND for the fuel pump and fuel gage is G-401. It is in the drivers side rear wheel well on the side of the frame. Its a stud with a 10mm nut. Carefully remove it and make sure that the frame and eyelet are clean and tight.
Please let us know how your troubleshooting efforts work out:
Here is an early fuel pump schematic but it shows power and ground:
Hope this helps
Bill
I have a BIG HEART when people in other countries attempt to work on cars that are this USA COMPLEX!
I will do what I can to assist you with your C5 issues.
The very first place that i would start would be the IGNITION SWITCH.
Here is a post that will allow you to repair your switch. Before you DIG INTO SWITCH REPAIR,,,, use a DC VOLT METER and measure the voltage on the fuel pump fuse to chassis ground. There are TWO TEST POINTS on top of each fuse. Measure eash test point to ground. You should see FULL BATTERY VOLTAGE when the ignition switch is ON.
- C5 ignition Switch repair - http://forums.corvetteforum.com/c5-t...ch-repair.html
If it reads normal, read the test points again when the relay is having it issues. I believe that you are at times UNDER VOLTAGE because the contacts inside the ignition switch are burnt and pitted.
The GROUND for the fuel pump and fuel gage is G-401. It is in the drivers side rear wheel well on the side of the frame. Its a stud with a 10mm nut. Carefully remove it and make sure that the frame and eyelet are clean and tight.
Please let us know how your troubleshooting efforts work out:
Here is an early fuel pump schematic but it shows power and ground:
Hope this helps
Bill
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Karl, another great way to get help is to use Skype or the Google equal (both free). Talking with someone using a webcam face to face to work through and explain issues is a great way to solve problems that are hard to put in a written message. I will monitor this and help anyway I can.
Thread Starter
Cruising
Joined: Jul 2013
Posts: 13
Likes: 0
From: Ludvika Dalarna
hey bill thanks again for all the tips and help is incredibly thankful 
I have full bateri volt fuse to the fuel pump 12'5 volts. 'll check on the key switch and it is new've checked all ground connections and clean them and some I have changed all the modules I have changed and all the contacts are clean and changed. brublemt the relay is that when I turned on igniskon start the relay to tick all the time and I have troubleshoot some time until I came to tac module when I removed the power plug to the module when the relay works as it should rotate ing starts the fuel pump and works in 3 sec and they are as they should be. and have checked all the wiring harnesses and clean them. my question is now Bill C if you can start the car without tac module. I will post utt some pictures of my Projeckt flloodet corvette c5 50th thanks again to Bill C and I raporterar how it goes
I have full bateri volt fuse to the fuel pump 12'5 volts. 'll check on the key switch and it is new've checked all ground connections and clean them and some I have changed all the modules I have changed and all the contacts are clean and changed. brublemt the relay is that when I turned on igniskon start the relay to tick all the time and I have troubleshoot some time until I came to tac module when I removed the power plug to the module when the relay works as it should rotate ing starts the fuel pump and works in 3 sec and they are as they should be. and have checked all the wiring harnesses and clean them. my question is now Bill C if you can start the car without tac module. I will post utt some pictures of my Projeckt flloodet corvette c5 50th thanks again to Bill C and I raporterar how it goes
Thread Starter
Cruising
Joined: Jul 2013
Posts: 13
Likes: 0
From: Ludvika Dalarna
3sacrowd / Dadaro thanks for helping me is not so good at spelling in English because I'm dyslexic and they are not easy, but I can speak fluent thanks again to you helps me incredibly grateful and best corvvete forum
Last edited by Drakos82; Aug 6, 2013 at 06:07 PM.
Melting Slicks
Joined: Jan 2004
Posts: 3,012
Likes: 15
From: Jensen Beach FL
That's o.k. Karl. Most of use can't speak or write Swedish so you are doing fine. I could interpret your post pretty well and Bill is very good at electrical issues so you are in good hands.
Thread Starter
Cruising
Joined: Jul 2013
Posts: 13
Likes: 0
From: Ludvika Dalarna
hey now, I have made great progress corvette starts and works and no error codes on the pcm I have replace tac module and the gas pedal and they work very well problem is the fuel system. I think I have an internal lekage., I have changed the fuel pump and then I had 50-60psi and now I have only 3 psi so I have to take down the fuel tank again they are not funny at all
then I connected an external fuel pump and when the engine works very well now remains pro code programming with tech2 will surely hear from me more
corvette starts and works and no error codes on the pcm I have replace tac module and the gas pedal and they work very well problem is the fuel system. I think I have an internal lekage., I have changed the fuel pump and then I had 50-60psi and now I have only 3 psi so I have to take down the fuel tank again they are not funny at all then I connected an external fuel pump and when the engine works very well now remains pro code programming with tech2 will surely hear from me more