Tachometer Swap Questions

[SlowGoing]

Hi all,

So to preface this question... I have indeed searched, many times over! And I've read a lot of the articles about this topic, but if I have missed something, please feel free to call me out.

My question concerns installing a tachometer in my 1982 Westy. It was originally a diesel but then was converted to a 1.8 gasser. I plan on installing a tach in it, but in the interest of maintaining an OEM look, I'd rather swap in a VW tach than install an auxiliary one. An ideal candidate for me would be installing a tach from a similar vintage Golf/Jetta/GTI, such as this one:

http://www.ebay.com/itm/VW-Golf-Jetta-Mk2-GTI-16V-...mp;vxp=mtr

I've read that it's difficult to swap these into WBX Vanagons because they run off the W terminal from the alternator. I've also read that swapping a WBX tach into a diesel is out of the question. So essentially what I'm getting at is: is it possible to swap the above tach into my 1.8 gas Westy? Has anyone successfully done this? (I have seen it done in a wbx vanagon, but I'm specifically curious about this engine)

Many thanks for the input!


P.S. FWIW, my engine is an RV code 1.8 from a 92 (iirc) Jetta.

[Syncroincity]

Forget the diesel tach, these are not applicable to you. RPM range is lower, and you probably don't have a W terminal on the alternator (although it's pretty easy to add one). The one in the Ebay ad is a gasser tach; observe the 6.5K redline. This WILL work, however, you will also need a newer Vanagon gasser ribbon cable at the very least, or be prepared to do some wiring and soldering; your instrument panel is not equipped to run a tach. I feel it would be better for you to just look for a OEM complete instrument panel with a tach already in it, you'll probably spend about the same money as that MKII unit, and it's less work.

Here's one in the classifieds now, but it's a little pricey at $250

http://www.thesamba.com/vw/classifieds/detail.php?id=1650246
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'86 Syncro CHC Top AAZ Turbodiesel
'04 Passat Variant 4Mo 5MT

Vanagon Build: http://www.thesamba.com/vw/forum/viewtopic.php?t=466866&highlight=

[MarkWard]

Also there are at least two Vanagon gasser tachs. The early 84-85 ones worked with the 1.9 engine management. The 86 and on tachs worked with 2.1. What engine management system are you using on your conversion?
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[SlowGoing]

Not sure about the engine management, unfortunately... the swap was done in 1996, long before I owned the car, and the documentation is slim to non - existent. I'll check up on it though.

Ah, I had forgot about the notorious ribbon cable... am I understanding you correctly, then, that I couldn't just run a separate wire from the GTI tach back to the W terminal?

I'd love to get the 83 - 85 cluster, but my main worry is that the tach seems to run off of a wire that I'm not sure my engine has (based on the instructions here: http://www.oldvolkshome.com/late_van_cluster_install.pdf). How could I make it work with a later vintage 1.8 gas engine?

Thanks so much, everyone!

[MarkWard]

My 82 did not have a tach and the circuit foil was toast. I bought a complete cluster from an 86 with the T12/T14 plug. It was really quite simple to install. I used the oldvolkshome pdf for rearranging the wires.

You just need an rpm signal to work the tach. You can get that signal directly from the negative side of the coil. Even aftermarket tachs utilize this rpm pulse.

I would suggest you get your ECU part number and Google it. You should then be able to determine what your engine management system came out of. Then you can find a wiring diagram to determine if the ECU has a tach output.

I have a project van with a Tiico conversion. It has a system from a vehicle not sold in North America, but I was still able to find a pdf to get it up and running by using the ECU part number. If you intend to keep and drive this van, you will need to know all of this anyway. The tach is the least of your problems at this point.
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[SlowGoing]

Ok, great! Did you have any issues calibrating the tach?

[SlowGoing]

I also checked my ECU -- It's a Bosch Digifant DF1 from an early 90s RV code Jetta. The part number is 0 261 200 554.

I'm going with the WBX tach cluster, I've decided, so I'll update the thread in a couple weeks when hopefully everything is done.

[a2d2]