Volkswagen: HELP, waffle iron, air sensor

Question
My 79 VW with 15,000 original miles just won't start anymore. This is my 5th VW, but first fuel injected.  I have a feeling it is the fuel pump.  I don't smell gas anymore when I turn it on.  It just won't turn over.  I was referred to you for "correct testing procedures" on the fuel pump, injector computer or number 3 cylinder temp sensor.  I am a Baby Boomer 58 year old female so be gentle! My husband is a mechanic but not good with fuel injection.  He did test the sensor I believe and said it was "plugged in".  HELP before I have no choice but to get it towed to a shop.  Happy New Year and thanks for being there.

Answer
Hi Susan,

No problem, you will get it working. The fuel injection is very hearty.

1) Take off the air filter (the black thing to the right of the intake air sensor).  The Air Sensor looks like a waffle iron from the top.

2) Just inside the air sensor is a flap that can be pushed with your finger.

3) Put the ignition switch on 'on'.  Put your finger in the square hole where the black plastic air-filter housing connects to the intake air sensor, and push the flap open.
This should kick on the fuel pump. You will hear the fuel pump quietly running in the front if it is ok.

4) If you do not hear anything, (which I would doubt) write me back and we will troubleshoot the fuel pump circuit.

If it does kick on, and the engine will not run, and you cannot smell gas from the exhaust after trying to crank it over, most likely, the problem is that the injectors are not getting a signal to 'open'.

Check the following:

1) Is the fuel filter new?  If not, replace it.  It is located under the front of the car, under the gas tank and is a white color. Silly item, but sometime the painfully obvious applies...are you sure there is fuel in the car?

2) There should be a white wire on the negative (-) connection of the ignition coil.  This white wire tells the fuel injectors to let fuel into the motor, based on the points opening and closing.  Make sure that wire is on nice and tight.

3) As mentioned above, the ignition points deliver the signal to the injectors, so they need to be clean, in good shape, and gapped properly.  The points are located under the distributor cap, connect to the condensor, and than a green wire runs from the condensor to the ignition coil (-).

4) There is a double-relay on the passenger side of the car, behind the rear seat back under a cardbord cover, and next to the fuel injection computer.  It is a called a 'double relay' because it has two functions:

1) When you first start the car, it tells the fuel pump to run as the starter is being turned over.  2) Than, it's next job is to switch the fuel pump over to run only from the flap you just pushed with your finger once the car starts. (as explained earlier).

Sometimes the double-relay plugs come loose or contacts get dirty over time, you may want to check that as well.  A good initial check is when you first turn the ignition to 'on', you will hear a healthy 'click' of the double relay.  If you do not hear that, again, let me know, we can check that circuit out.

I'm sure this is enough to make some deductions, and hopefully get you running by the new year.

Please keep me posted and I'm only glad to help!

Ron