348 Speedometer Pulse Sensor Repair - for dead speedometer

Hi guys, my speedometer on my 1993 348 died last week. There are a couple of things it could have been, but 90% of the time it is this part that goes bad. This repair took less than 15 minutes (with the right tools). Let's get started.

 

The part is #29 on this diagram. I got it from Ricambi (shout out to Daniel), it is just under $300

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Here it is
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You will also need a new gasket, which is #30 on that diagram (less than $1)
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List of tools required:

1) half inch ratchet
2) 1-1/4" (or 32mm) deep socket - has to be a deep socket, and you will see why
3) u-joint, because the location of this part is very awkard and hard to get to with just the ratchet and socket
4) 2' extenstion bar

 

Here it is looking in, standing right in front of the back left tire. It's the part to with the light shining on it, to the left of the Iphone when staring at the iPhone straight on (so underneath the iPhone when looking at it in this picture). You can see the wire plug there as well, that needs to come undone.
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Another view, this time looking in from the back of the car.
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Once you have unplugged the wires (there's not clipt, they just snug together), feed the loose end of the plug inside the socket (that's why it has to be a deep socket, so you have room for the wiring plug) and snug the socket into place. I had the u-joint, and the extension bar fastened while doing this, so all I had to do was snap on the ratchet once everything was in place. In this picture the extension bar is not on, just the u-joint, I left it off so I could take a picture to show this part. This view is from the side of the car, looking in from the rear left tire.
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Another view, from the back of the car this time.
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This is what it will look like when you are ready to loosen and then refasten. You see what I mean by it being in a very difficult location, hence the extension bar and u-joint.
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Once I removed the old part, I saw exactly what was wrong.
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Compare this pic to the one in the previous post. One of the wires came loose. If I had taken the part out, before ordering the new one and saw this, I would have tried to repair first. But it's all good, I'm not concerned about that, at least now I have a spare unit (once repaired of course) and I would be happy to pass it on to a 348 brother in need.
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Here's another shot of the tools in place for the job
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Once you have the old part out, you can easily spin on the new one until you can't spin any longer, attach the socket, and snug it up. Re-attach the wires, and you're good to go.

 

And the finished product - I'm back in business
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And here you will see why you need a deep socket as opposed to a regular (shallow). The wiring will not fit in the shallow socket.
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You will still have to bend the wire to fit into the deep socket, but word of caution, bend it at this location only, do not bend it at the base of the wiring (the part that goes into the metal)
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There are likely a couple ways to do this (ie maybe remove the tire and go in from the wheel well), but I found this the quickest and easiest, and it did the job.

There you have it, a quick and easy repair for this part!

 

I saw that you posted this in the other thready as well, but I didn't feel like tinkering with splicing wires etc....and it isn't a huge difference in $$...I'm the plug-and-play type guy!

 

Oops - forgot that part in my thread (and Ernie you get credit for this, I copied this from the 348 parts sourcing thread that you posted):

Ferrari: 116987
Alfa Romeo: 60575205
Maserati: 393650106
Veglia Borletti: 680517

This part is actually hard to find, luckily Daniel had one in stock, but there are a few places in the US that do have it in stock. Any of those will work, but I used the 116987 Ferrari part.