M758

Wow...
Saturday I chanced the speed sensor on my race car. Took me 5 minutues with the car still in my trailer. 1 bolt and 1 electrical connection. Sadly swapping the sensor did not address my issue so I moved on.

User 52121

When I swapped mine out, I fought with it a bit but now after doing it, the next time around it won't be so bad.

Removing the intake manifold certainly makes it a little easier, but it can be done without it, and I have very large hands. The hard part for me was actually getting the sensors out of the bracket. Wound up hitting them with WD-40 and kinda working them in and out for a few minutes (with more WD applied) and they eventually slipped out nice and easy. Unfortunately I hammered on them for an hour BEFORE I thought to try some kind of lube and for sure broke 1 sensor, and didn't trust the other, so I replaced them with new BMW ones.

So my advice: plug the flywheel hole, just cram your hands down there (they'll fit), get the bolts out (your magnet tool will be handy for getting them out without dropping), and slowly work the sensors out. They'll probably come out 3/4 of an inch or so and stop. Coat the body with WD or grease or something, then just kinda work them in and out, they'll eventually slide out. When you put them back in, put some anti-seize on the sensor body that sits in the bracket.

Be careful about twisting them. The metal part of the sensor is NOT supposed to rotate relative to the plastic body. If it rotates at all - it's broken.

porschefig

Once we moved to our house I left the car alone for a couple months.
Today, I went for try number 2.

Got the intake off and the first sensor pulled right out. Easy! I can see that it would only take 5 minutes....
The second one won't budge! I can't get it to lift ANY. Tried vice grips and prying under it... nothing. Do the sensors mount in a removable block or are the two hex head bolts for the "bell housing??"

Bri Bro

Soak it in PB blaster a couple of days. They get dirt and sand in the bore and almost weld themselves in. The bracket comes off with two screws if you can get to them. You will need to check the sensor clearance before you crank the car.

JimV8

I guess it depends on how long they've been in there. The front one came out OK, the back one came apart.

Mike C.

I don't know how you guys can do these with the intake on... I've tried and finally pulled the intake..

porschefig

Exactly, the back one is breaking and I'm worried that it's only getting harder to get it out!
I guess my next try is to remove the metal block from the bell housing that the sensors are inserted in...
Hopefully this isn't too stupid of a question: why would the sensor clearance change? They're the same length and they're bolted right down... Is the height of the block they're mounted in adjustable?

Bri Bro

Yes, the height is adjustable. There are slots on the sensor block to adjust the height.

67King

Use one of these:


and one of these:


And you'll have them out in about 30 seconds.

KuHL 951

Did I miss the post or did you ever find the lost bolt?

944Ross

...unless there is corrosion between the SS case and the aluminum of the bracket, which the rear one seems to be prone to. I had to use visegrips clamped onto the head, and pry the visegrips with a long screwdriver to get mine to budge. Rotating back and forth helps break it loose.

M758

I have pulled both of mine a couple times and even adjusted the height. All with the intake on. 944 NA of course.

Getting to both adjuster bolts was a little hard, but alot easier than taking the intake off.

JimV8

The sensors have a metal can that in my car was corroded tight in the hole of the bracket. There was no choice but to remove the bracket and then punch it out in a vise. I don't recall it having any adjustment though, mine was an 85.5.

944Ross

One bolt is a pivot point, the other in a slot

porschefig

:-) Yeah, I bought a magnetic pickup with a light on the end of it (I was working outside when we were living in an apartment) and got it out no problems! Since then I towed the car over to our new house and have left it sitting in the garage for ~2 months. Out of sight, out of mind! (but a DE at Pacific Raceway is getting my rear in gear!)

Are the bolts for the sensor block 6 mm allen head? I have a set of metric of allen wrenches. The 5mm is too small and the 6 mm allen wrench is too long to engage with the bolt (hits the fire wall). I'm going to go buy a 6 mm allen head socket but want to confirm!

Thanks for all the help so far!