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Discussion Starter · #1 ·
Please excuse my ignorance but will a fuel pressure that is 4psi lower than what the manual calls for cause a no start condition?
I put a pressure gauge in a T connection in the fuel supply line. After cycling the ignition on and off several times the highest reading I get is 40 psi and the manual calls for 44psi. The pressure does spike at 44 as soon as the pump activates but then immediately drops back to 40. After a 10 minute wait the pressure is at about 35-36 psi. I have no idea what it is with the car running because it won't start. Any input would be appreciated.
 

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Hey, what year is the car? Where along the fuel system; have you put the fuel pressure tester? I would follow the service manual; for step by step testing. Pressure testing without the car running; is not a good indicator, of whether the pressure is good enough for the engine to run as it should. Fuel filter replacement; is a cheap easy way to see if it is clogged and probably needs to be changed anyway. The manual; also, has testing for fuel pump (volume) vs. pressure.

Can you tell us more; about the history of the problems you are/were having; have you checked for trouble codes and spark from the ignition?
 

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Discussion Starter · #3 ·
The car is a 2000 Beetle with the 2.0 gas engine.

I wish I could give a lot of details about the car but I purchased it as a project car and it was not running. I have tested each plug with a spark tester and I am getting spark. The engine turns over fine but just won't fire. I put noid lights on all of the injectors and they look like they are firing ok. I was able to check the resistance of 2 of the injectors without taking the intake off again and they are in spec. The funny thing is, I took the intake and valve cover off and put it back on and the thing actually started and ran for 2-3 seconds but not since. The imobilizer light is not on and I don't see a code set for it.
I started looking at the fuel side and the manual has me check the initial pressure and it is 4psi low. If I plug the return line it doesn't change anything. I might change the filter just for the sake of doing it but if I just let the pump run into a can it seems like it is flowing ok. I didn't see how to do the volume test. The pump runs for a few seconds than stops.

Not sure what else I can say :confused:
 

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Hmm, well; here are the fuel pump testing procedures. I had a VW Jetta with a 2.0L; it had fuel pressure in spec but the fuel pump, was still bad. I think; if I had done, the fuel volume test it probably would have been wrong. I would also; check the fuel pressure regulator. Look in the manual for the test for that as well; if you remove the vacuum line and fuel comes out, that is a sign it is bad but also look at the specs, they reference as well.

fuel pump pressure:

Volkswagen Workshop Manuals > Beetle L4-2.0L (AEG) (2000) > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure > System Information > Specifications > Pressure, Vacuum and Temperature Specifications

fuel pressure regulator:

http://workshop-manuals.com/volkswa...re_regulator/component_information/locations/

If you decide to replace the fuel pump; the Bosch unit from amazon; is the best price and we have had great feedback from it so far.


Turbine Fuel Pumps

Bosch state-of-the-art turbine fuel pumps offer many advantages when compared to older roller-cell and inner-gear pump designs, while significantly reducing wear and delivering a longer service life.
Key Features

Virtually eliminates fuel pulsation for drivability and longer life
Bosch impeller ring for smooth fuel flow and reliable performance
Precision, spin-balanced and polymer-encased armature for reduced noise

Part number: 69740

This part compatible with: 2000 Volkswagen Beetle L4 2.0L

http://www.amazon.com/Bosch-69740-O...automotive&vehicleId=9&vehicleType=automotive
 

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Discussion Starter · #5 ·
I appreciate all of the info. I looked at the page for the manual about the volume test and would like to try it. How do I get the pump to run long enough to do the test? When I turn the ignition on, the pump runs for a few seconds to prime then it shuts off. If I relieve the pressure by way of the relief valve on the gauge it does not continue to pump fuel. What to I have to do to get it to keep pumping?
 

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Hey, you will have to try it but I think, it will keep going because the fuel pressure will not build up.... as you are delivering the fuel to a container. You need to try it out; to know for sure but I think thats the way it is. I would assume; the manual directions, will tell you how to do it correctly.
 

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Discussion Starter · #7 ·
I can't see where it gives the instructions how to do the fuel volume test. I only see what the volume should be at different voltages. Anyone have any ideas? Like I said before, when I turn the key to the run position the pump just gives a brief shot of fuel than shuts off. It will do that even when the supply line is unhooked from the filter and ran into a container.
 

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The Bentley's manual calls for making a jumper wire to go between the battery positive terminal and the fuel pump fuse socket. The jumper should have a switch in it to allow you to turn the pump on and off. The wire needs to be 14 gauge or better with a spade terminal the same size as the fuse blade. The fuel pump fuse is number 28 and the connection should be to the rear-most fuse terminal.
 
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