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Fuel pump relay been bypassed?

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I'm still having bloody fuel and starting issues. 

How do I find out if the fuel relay has been bypassed? And if it has, how do I correct it? There are relays hanging by the fuse box with wires attached and all sorts. Causing me a right headache. 

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what engine is it standard gti or a conversion?

Hello my name is John and I'm a dub addict.



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Damn, sorry forgot to put any details! 
It's an 1989 cabriolet gti. It's as standard as far as I'm aware.

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ok the fuel relay is in slot 2, pull it out and see if the pump still runs. if it does, yes its been bypassed! let us know the number on the relay too

Hello my name is John and I'm a dub addict.



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Ok, so when the ignition is on click 1 the pump starts to whine, the pitch changes after about 2 seconds and it keeps on whining. If I remove the relay nothing happens at all. When the car is running you can hear the pump whining still, when I removed the relay the whining stopped and the car continued to work fine. However once I turned it off and back on one click it was still whining. It's a new relay I purchased from euro car parts, 321 906 059F

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that one should only be fitted to JH code engines apparently, but I believe it should work fine though.

chase down the source of the whining, if you pull the relay it should kill both the fuel pumps and stop the car. if it doesnt then you have your main pump on an ignition feed or there is some kind of short between an ignition and pump feed or something.

chase all the relays that arte hanging about the place, chances are its an alarm system and if tapped into the fuel loom this could be why it doesnt kill the pump when running, but it does when you pull the relay before you start the car

Hello my name is John and I'm a dub addict.



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When you start a car, the first click of the ignition switch is called run.  The fuel pumps prime for 4 seconds.
This pressurizes the lines to assist and end vapor lock or hot start issues.

Now that you say it is whinning, that is because the main pump is over working to get fuel to the engine.

This can be caused by a bad filter.
Or anything from the lifter (in-tank) pump, to the main pump.

On the CIS this can be caused by the Accumulator or sump as well.

A bad ground can also be a issue some times as well.

The in-tank or (lifter) pump can fail because of rust particle in the tank.  The Pump has been run continuously on less than half a tank as you only put a couple of bucks of fuel in it.  The lifter pump uses the fuel surrounding it as a coolant and lubricant, so reduced fuel causes it to over heat and start failing.

The Lifter pump is also connected to the sending unit feed thru by a rubber hose that can hole (split) and or separate there by reducing the fuel to the main.

Removing the Fuel Pump Relay, removes power to both pumps, so nothing will work. (don't do that!).

If the main pump over works too much it will take a dump and you will have to replace it and still resolve the major cause of it's demise.

What do Divorces, Great Coffee, and Car Electrics all have in common?

They all start with GOOD Grounds.

Where are my DIY Links?

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I had replaced the lift pump around 3 weeks ago, hoping this was the issue. No such luck. 
The whining noise isn't bothering me so much, it's the constant turning and turning before the engine fires up, and it is very slow and stuterry when it does fire up. I had presumed this was all linked but not sure. Any ideas? 
Do you think it's worth me just removing the alarm and the 1000's of wires attached to it?!

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I mean chase it down to figure out if it is a fuel pump that is the cause of the noise. if it is one of the pumps then you know its still being controlled by the fuel relay as it cuts out when the relay is pulled.

the main pump must be powered from something else for sure, as there is no way a kjet car can run without this.

if it has an alarm as I say that would be my first thought, if the wiring to it is poor then I would certainly consider stripping it out anyway.

Hello my name is John and I'm a dub addict.



My wiring diagrams and other documents have moved here:

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Ok nice one cheers. I've had enough messing about for today, so back on it tomorrow. Why is nothing ever simple!

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Adammmm said

Ok nice one cheers. I've had enough messing about for today, so back on it tomorrow. Why is nothing ever simple!

Ignoring a Whining pump, isn't going to resolve the issue.
Getting the correct fuel pump relay will.  If the pumps run for more than four seconds on key on run position, then that is the relay.

Whining pumps isn't the relay usually and ignoring the issue is going to be more costly to repair when it stops altogether.



What do Divorces, Great Coffee, and Car Electrics all have in common?

They all start with GOOD Grounds.

Where are my DIY Links?

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The relay that was on the car, which was the genuine vw one, I replaced a couple of weeks ago, and it made absolutely no difference. 
I will get the car jacked up tomorrow and find out exactly what is whining. 
This whole issue is driving me mad. 
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