Fuel injection wiring harness

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Fuel injection wiring harness

Post by dennisvwman » Thu Jun 08, 2017 12:45 pm

I have a 1978 VW super beetle convertible. I have been following the orange Bentley book and other documentation
in trying to get it started, trouble shooting the fuel injection, etc. My double relay looks O.K. Every step to make sure
that it is working has been checked. I.E., electrical contacts where my test light goes on in checking the double relay
numbers; 85, 86A...88, etc.

The Bentley book mentions if you have checked everything and the car does not start, it could be wiring. My car has
been garaged for many years, so I do not think the weather has taken a toll on it. I have traced all the fuel injection
wires, connections, etc. and no luck in getting the car started.

The wire connections to the double relay behind my back seat look O.K., but just in case I would have to replace some
wires, what size are the fuel injection wires? Also, in the engine compartment, those wires look O.K., but again if
I were to replace the wires, what is the wire size going to the Temperature Sensor II to the number 4 cylinder, the
resistance block, to the fuel injectors, etc. I have checked on various VW internet sites and the wiring harness for
the 1975 - 1979 fuel injection engine are not made anymore. Most likely a remanufactured wiring harness or one
from old VW is all I am going to find. Finally, I know the Bentley book shows the wiring diagrams, but I not sure
what the wire numbers mean or how to interpret them.

If anyone can help me with my issue that would be great.


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Re: Fuel injection wiring harness

Post by risk » Thu Jun 08, 2017 3:53 pm

I have had issues with old fuel injectors sticking.. try spraying some starting fluid and crank it. If it tries to crank you can rule out ignition and focus on the fuel side. IF the injectors are stuck, sometimes some light tapping on them will free them up.

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Re: Fuel injection wiring harness

Post by Piledriver » Sat Jun 10, 2017 2:26 am

Welcome to the STF!!!

Just sitting takes a huge toll, esp if there was any gasoline in the tank.
It's not really gasoline after many years, its a tank of varnish, almost guaranteed to foul plugs and possibly bork the fuel system in many interesting ways... (in the "may you have an interesting life" Chinese curse way)

Also: Mice eat wiring for a hobby when bored.
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

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