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Discussion Starter · #1 ·
98 beetle 2.0 gas. This car belongs to a friend of mine, she intermittently had no no start issues until a few days ago when intermittent became permanent. I noticed that I did not hear the fuel pump kick on when the ignition key was turned on .So that's where I started troubleshooting. I dug around the forums and I haven't found anybody had this specific problem on this model: No fuel pump relay. Looking at the position where 409 should be, they were contacts in the plug, but there was no relay there. I can say with 100% certainty that she didn't remove the relay suddenly one day, it seems as though it hadn't been there at least since she owned the car.


Given that this model year was supposed to have a relay for gas driven vehicles my only assumption is that a previous owner somehow managed to bypass it successfully and not break all of the other components that relied upon it.

When the ignition is turned on, I get 12 volts at the fuse for about one second and then it drops to around one volt, same results occur at fuel pump itself. I'm at a bit of a loss as to exactly how to proceed here except to remove the source wire from the fuse and feed it with an ignition switched line. Now, don't go chastising me for bypassing specific safety measures put in place, but as a temporary solution I do need to get the vehicle going and go back later to figure out exactly what went wrong.

Which takes me to why I'm here: what conditions must exist for the computer to feed a 12 volt source to the fuse box for the fuel pump? What I would like to do is isolate all possible causes individually. As I said, until recently it worked most of the time, which means those conditions were being met and now at least one of those conditions is not being met.

As a secondary question, is there a standard bypass mod as in use for bypassing the fuel pump relay on these cars so I can look for that specific configuration to see if it exists?
 

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http://newbeetle.org/forums/questio...etle/34728-where-fuel-pump-relay-located.html

Since the car is a 99 model year, I would also bet the fuel pump should be replaced.

Sounds like the prime cycle electrical function is working.

You can pull the rear seat bottom and remove the access cover t the fuel pump. Use the butt of a hammer to tap firmly on the pump collar and you might be able to get the car started.

My vote is to replace the fuel pump and relay as the car is probably close to 18 years old!
 

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Discussion Starter · #3 ·
I guess I left a piece of information out. I actually applied 12 volts to the fuel pump and it fired up just fine so the problem is the 12 volt source not making it to the pump. I'm very hesitant to put a relay in there given that somebody has obviously bypassed the relay is everything was fine a few days ago and the relay was not present at that time.
 

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I guess I left a piece of information out. I actually applied 12 volts to the fuel pump and it fired up just fine so the problem is the 12 volt source not making it to the pump. I'm very hesitant to put a relay in there given that somebody has obviously bypassed the relay is everything was fine a few days ago and the relay was not present at that time.
Explain "fired up just fine".

What "fired up", the fuel pump or the engine?

If the engine started, then the crank sensor is not likely a problem.

I would say time to get a relay and install it??
 

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Discussion Starter · #6 ·
This afternoon I clip the wire that feeds the fuel pump fuse and routed I've known good switched 12-volt source to the fuse. The car runs just fine now. Granted, the rollover switch if there is one, is probably bypassed, but she needed her car running.

I'm not going to install a relay into a circuit that has been modified in some unknown way until i at least discover what way that was. If it ran without the relay before, that means the circuit is not in stock state and throwing a relay into it would cause more problems than it would solve.
 
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