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Old 12-27-2009, 10:40 PM   #1
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Default Help with fueling problem please

So earlier today I was doing some work outside and a buddy of mine stopped by and asked me to help him with his 02se. I know nothing about nb's but I said I would try and help.

Long story short, the car was running and then stopped. The fuel pump relay was replaced and the car ran fine for a week. Now it won't start. The relay was tested and the relay is fine.

So anyway, he took me to see the car and it started. The car turned Off after a minute of running. Now my electrically enclined friend came over to lend a hand but, unfortunately the three of us have not reached a solution.

Any info or ideas will be most appreciated. Sorry for speeling/grammar, I am using my friends iPhone.

Edit: we pulled the pump and jumped it manually for a few seconds. It turned on fine. The owner is now thinking it might be the fuel pressure regulator on the "return"?

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Old 12-28-2009, 12:11 AM   #2
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Since it seems like all of this has happened after the pump was replace so I'm thinking
-Wiring got bumped around by the pump meaning there is a loose wire somewhere
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Old 12-28-2009, 12:46 AM   #3
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NB's use a returnless fuel system, there's no FPR, at least on the return as there is none. The regulator is inside the tank. You need to rent a fuel pressure test kit from Autozone or Oreillys and find out if you are getting normal fuel pressure at the rail, 60psi IIRC.

Is the pump getting normal voltage at the connector? at the relay?
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Old 12-28-2009, 01:09 AM   #4
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OK HERE IS WHERE THE **** GETS CRAZY: Over the course of the 5 hours we worked on this NB we used a voltage/ohm tester (multi meter?) and tested every signle ******* connection we could thing of.....there was power to everything, ie: pump, connections, all wires and assembly. But still the pump would not turn on when in the tank.

So the owner had a great idea to use a piece of wire to bypass/jump the fuel pump relay and still it would not start.

NOW WTF??? We are all standing around scratches our heads trying to think of a solution. I said, "what the ****, try to crank it again." And guess what? The damn car starts with the bypassed/jumped relay wire we ghetto'd in place. So we take the wire out and put the relay back in....and the car starts up and runs strong. We turned the car off and on, off and on....runs great.

BUT WHY??????
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Old 12-28-2009, 01:11 AM   #5
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Quote:
Originally Posted by ARTech View Post
NB's use a returnless fuel system, there's no FPR, at least on the return as there is none. The regulator is inside the tank. You need to rent a fuel pressure test kit from Autozone or Oreillys and find out if you are getting normal fuel pressure at the rail, 60psi IIRC.

Is the pump getting normal voltage at the connector? at the relay?
Thats what I told him but, he swore there was a return

There is normal voltage to everything. That is whats freaking us out.
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Old 12-28-2009, 01:13 AM   #6
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Quote:
Originally Posted by Jester of Paint View Post
Since it seems like all of this has happened after the pump was replace so I'm thinking
-Wiring got bumped around by the pump meaning there is a loose wire somewhere
Only the relay was replaced and the wiring in/around/to the pump is normal.
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Old 12-28-2009, 01:29 AM   #7
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So it's working fine now? Problem solved?

If not, my guess is another bad relay and possibly a dying pump. How many volts at the pump connector with the relay in place? How about with the jumper wire? The engine may not have started the first time around because fp was not built up yet (next time it doesn't start prime it a few times before starting), and the normal starting following could be attributed to residual pressure.
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Old 12-28-2009, 01:45 AM   #8
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Quote:
Originally Posted by ARTech View Post
So it's working fine now? Problem solved?

If not, my guess is another bad relay and possibly a dying pump. How many volts at the pump connector with the relay in place? How about with the jumper wire? The engine may not have started the first time around because fp was not built up yet (next time it doesn't start prime it a few times before starting), and the normal starting following could be attributed to residual pressure.
We had the relay tested and it's perfectly fine, we even had the original tested and it too was fine.

12-13"?" volts at the pump and all around. We tried to crank the car a zillion times but, never heard the pump kick on. Then it just decided to work

So, my guess originally was a slowly dying pump and it still is. The owner is going to pick up a new assembly tomorrow, so if it turns out not to be the pump...oh well. Atleast he'll have a back up.

The car runs perfect, like really perfect. For how long? Who knows....
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