Ken, according to my Jetta Bentley for that year, the MAF sensor
red/blue wire you refer to should have power whenever the fuel pump is
running. It's power comes from current track 16, brought to there on
relay panel track "a" which comes from the fuel pump relay output leg,
4/87 on relay J17. The ECU controls whether the fuel pump runs, by
controlling the ground leg of the fuel pump relay coil 3/85 of relay
J17. Of course with a conversion the installer may mouse around with the
fuel pump control but it is best to do it like the factory did so the
pump shuts off unless the engine is running normally or trying to start.
There are a few other devices that also get power from the same source
so make sure that the other devices with a wire of the same color are
also connected to it.

Mark

Kenneth Wilford wrote:

>I think I have found a problem with the wiring harness on the conversion
>I am working on.  The wiring harness is from a 97 Jetta with the 2.0l
>ABA engine.  Anyway the wiring harness has a four wire plug on the mass
>air sensor.  One of the wires is red with a blue stripe.  If you have
>the Jetta Bentley Manual it is on page 97-297.  This wire goes to a
>group of other wires that are the same color and they hook to what is
>called "Plus connection in Multiport Fuel Injection wiring harness".  On
>the wiring diagram this is called E7 however the wiring diagram also
>calls it 87a.  What I think is going on is that this wire is the power
>for the heated air mass sensor.  But I don't want to hook up power to it
>if it isn't supposed to get power as I don't want to fry anything.  Can
>anyone help me figure this out.  Also is this wire supposed to be full
>time hot or just hot when the ignition on.
>
>This wire was cut and not hooked to anything when I got the conversion.
>The van runs but only when it is warm outside and also it doesn't seem
>to have a lot of power.
>
>Sorry but I am not super familiar with the whole mass air sensor thing.
>
>Any help you can give would be apreciated.
>
>Thanks,
>Ken Wilford
>John 3:16
>http://www.vanagain.com
>http://www.strictlyvwauctions.com
>http://www.eurovan.org
>http://www.vwcabrio.org
>Phone: (856)-327-4936
>Fax: (856)-327-2242
>
>
>