c5 fuel pump problem, need help asap tried a few things
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From: Palm bay Fl
c5 fuel pump problem, need help asap tried a few things
Ok, so I have a 2000 corvette, and about 3 weeks ago I started the car and it just died, (sputted to a stop) started it again and it ran fine.. ran a few days with no problems.
Then it did the same thing, so I started it and it reved up then died, it did this several times and finally stayed running.
It did this a few times untill recently and now just wont run....
(diagnosis)
I noticed that the main fuel pump was not turning on when I put the key in ON position so I tried swapping the relay, this fixed it for about a mile then died while running. then wouldn't start....
I then replaced the fuel pump thinking it was that, it ran fine for 5 mins then died again... wont start. it is very intermittent, and the fuel pump wont turn on. (cannot heat r it when the hey is in on position)
What the hell else could it be, this is really bothering me. please help
Then it did the same thing, so I started it and it reved up then died, it did this several times and finally stayed running.
It did this a few times untill recently and now just wont run....
(diagnosis)
I noticed that the main fuel pump was not turning on when I put the key in ON position so I tried swapping the relay, this fixed it for about a mile then died while running. then wouldn't start....
I then replaced the fuel pump thinking it was that, it ran fine for 5 mins then died again... wont start. it is very intermittent, and the fuel pump wont turn on. (cannot heat r it when the hey is in on position)
What the hell else could it be, this is really bothering me. please help
Instructor
Joined: Jan 2012
Posts: 249
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From: Montgomery Co. PA
You need to put a fuel pressure gauge on it to see what happening to the pressure when it starts to cut out. Sounds ike something in the circuit is getting hot. Change one variable at a time. Take your time to find out the root of the problem. Throwing parts at it gets expensive.
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From: Palm bay Fl
I have a permenent gauge on it. It just drops to zero. And only starts up for a second just to doe again I am assuming because it builds a tiny bit of pressure from the secondary pump in the passenger tank by sending fuel to the drivers side. What else can it be?
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From: Dyer, IN
Ok, so I have a 2000 corvette, and about 3 weeks ago I started the car and it just died, (sputted to a stop) started it again and it ran fine.. ran a few days with no problems.
Then it did the same thing, so I started it and it reved up then died, it did this several times and finally stayed running.
It did this a few times untill recently and now just wont run....
(diagnosis)
I noticed that the main fuel pump was not turning on when I put the key in ON position so I tried swapping the relay, this fixed it for about a mile then died while running. then wouldn't start....
I then replaced the fuel pump thinking it was that, it ran fine for 5 mins then died again... wont start. it is very intermittent, and the fuel pump wont turn on. (cannot heat r it when the hey is in on position)
What the hell else could it be, this is really bothering me. please help
Then it did the same thing, so I started it and it reved up then died, it did this several times and finally stayed running.
It did this a few times untill recently and now just wont run....
(diagnosis)
I noticed that the main fuel pump was not turning on when I put the key in ON position so I tried swapping the relay, this fixed it for about a mile then died while running. then wouldn't start....
I then replaced the fuel pump thinking it was that, it ran fine for 5 mins then died again... wont start. it is very intermittent, and the fuel pump wont turn on. (cannot heat r it when the hey is in on position)
What the hell else could it be, this is really bothering me. please help
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
Thread Starter
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Joined: Jun 2011
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From: Palm bay Fl
Lu appreciated
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Tech Contributor
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From: Dyer, IN
I had one cheap and it only took an hour so I gave it a shot, didn't fix it apparently . I can see if there is 12v going to pump but how do I take a ground measurement could bad engine ground cause this? Is this a known problem. Thanks in advance car is still sitting any help is rea
Lu appreciated
Lu appreciated
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From: Palm bay Fl
Also when you ground those pins just run wire to neg side of battery? And what do I use for the 12v supply.
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From: Dyer, IN
I just got the message today, have been busy with work. I will attempt tomorrow, if it does fix it then what is the issue? I have swapped the relay out a few times with 3 different ones, hard to think there all bad.
Also when you ground those pins just run wire to neg side of battery? And what do I use for the 12v supply.
Also when you ground those pins just run wire to neg side of battery? And what do I use for the 12v supply.
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From: Palm bay Fl
Ground those pins? You are not "grounding" anything. What I have outlined, involves specific voltage checks, and a check for a good ground at the relay socket. You have to use a meter for both checks. The quickest way to verify the wiring is good from the fusebox back to the pump, is installing a jumper in the relay socket, which will cause the pump to run continuously (key on). Not sure what else I can do here. I provided the direction, a picture (labeled), and a schematic.
Thought you meant put a ground and 12v to those pins, didn't make sense but much doesn't for electronics and im not electrical savy obviously...what will a good ground read?
So if I do get 12v and a good ground than what? Is it the relay and or pump?
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From: Dyer, IN
0 to .3 ohms I'll let someone else take it from here.
Good luck.
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From: Palm bay Fl
Ok well, hopefully someone will help, I did the jumper in the relay and it worked pump turned on, So i figgured it was the relay, I just replaced it and it still wont engage the pump when key is in on pos. Ideas?
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From: Palm bay Fl
Also checked pin 86 by putting a volt meter and with the wires (pos red) onto the 86 pin, and (neg black) onto the ground of the battery it read 12.5 volts, how do I check the ohms of the 85 pin? or did I check this wrong.