# 1978 rabbit fuel pump relay and pump



## mchapa (Apr 28, 2010)

What is the location of the fuel pump relay ....is it under the dash????? The book says it is right above the 7th fuse above.....but the only thing I find is a connecter were the relay should be.....I do see a relay with a fuse on top of it.....but it is to the left.......
question #2...Should I have power to the fuel pump when I have the key turned to the " on" position?????? Or only when the engine is actually cranking??? Question#3.....where is the air switch...this is suppose to keep the fuel pump on after I release the key from the start position??????


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## ABA Scirocco (May 30, 2001)

*Re: 1978 rabbit fuel pump relay and pump (mchapa)*

First things first. Welcome to the Vortex.
1- That relay with the fuse, is the fuel pump relay. Originally, your car would have had the relay located in the position indicated by the book but VW found they were having an over heating issue with the relay in that location so, they issued a recall to fix the problem, the repair moved the relay above the fuse box connected with the harness seen in the picture below.
2- The relay is sort of a time delayed relay, it turns on the fuel pump immediately when you first turn on the ignition and then the relay checks to see if the engine is turning, by monitoring a tach signal from the ignition coil, if within 2 or 3 second, it hasn't yet detected that the engine is turning, it shuts off the fuel pump and doesn't turn it back on until it detects that the engine turning.
3- I've never heard of an "air switch", it's the tach signal from the ignition coil that keeps the fuel pump on while the engine is running or cranking.












_Modified by ABA Scirocco at 6:28 PM 4-28-2010_


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## WaterWheels (Aug 14, 2005)

*Re: 1978 rabbit fuel pump relay and pump (mchapa)*


_Quote, originally posted by *mchapa* »_ Question#3.....where is the air switch...this is suppose to keep the fuel pump on after I release the key from the start position??????


Might be a loose term used for something used in vehicles like BMW with L-Jetronic. The air sensor has a switch that allows the pump realy to stay closed as long as air is passing through it.


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## ABA Scirocco (May 30, 2001)

*Re: 1978 rabbit fuel pump relay and pump (WaterWheels)*


_Quote, originally posted by *WaterWheels* »_
Might be a loose term used for something used in vehicles like BMW with L-Jetronic. The air sensor has a switch that allows the pump realy to stay closed as long as air is passing through it.

In any event, there's no such thing on a 78 Rabbit.


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## mchapa (Apr 28, 2010)

*Re: 1978 rabbit fuel pump relay and pump (WaterWheels)*

picture can tell a thousand words.....


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## mchapa (Apr 28, 2010)

*Re: 1978 rabbit fuel pump relay and pump (WaterWheels)*

I have figured out that the pumps is bad.....removed it and connected it to a battery....it did not make a sound.....but the wire I used got warm........ I did have 12 volts to the pump but only when the key is on the start position.........Bought one for $77.00 dollars......at Carquest............Question...... this car has been sitting for 2 years......
Do I have to do anything to the fuel distributer??????


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