Username or Email Address
Do you already have an account?
Forgot your password?
  • Log in or Sign up

    VWVortex


    Results 1 to 6 of 6

    Thread: 1978 rabbit fuel pump relay and pump

    1. 04-28-2010 02:17 PM #1
      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??????

    2. 04-28-2010 07:25 PM #2
      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


    3. Member
      Join Date
      Aug 14th, 2005
      Location
      Germany
      Posts
      2,272
      04-29-2010 02:54 AM #3
      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.


    4. 04-29-2010 10:36 AM #4
      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.


    5. 04-29-2010 04:50 PM #5
      picture can tell a thousand words.....

    6. 04-29-2010 05:00 PM #6
      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??????

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •