Player0

Hey all,

My replacement speed sensor arrived. It was a bit of a nightmare getting the bolt out. Someone else rounded it off pretty good and it was seized. I'm looking to find a replacement bolt but haven't had much luck. Anyone know where I can find this part?

Also, would anti seize damage the sensor in any way?

Finally, I have yet to be able to remove the old sensor. I've loosened it enough to turn it left and right a bit, but I haven't been able to pull it out. Are there any tools that can help?

flightline

The bolt is just a regular M6x24 hex head bolt I believe. If you absolutely must have an original porsche part it's number 999 217 026 02 and pelican parts will sell you one for $14.25. But it's just a bolt, head down to your local hardware store.

I don't think anti-seize should damage it, I think it's a simple variable reluctance sensor and should be completely sealed.

To pull it out, have you managed to get a pair of pliers on it yet? I know it's in a tricky spot. . .

Player0

The original part has a hex head, and then a small cylindrical 'spacer' directly underneath. I think its so that pressure is put on the inner portion of the sensor's hole, but a regular bolt would probably work just fine.

Thanks for finding the part! I'll try a regular one first, and if that's no go, $14.25 it will be.

I haven't gotten pliers on it yet. To even budge, I attached vice grips to a large crescent wrench that fit over the sensor and twisted back and forth from a safe distance. I need to pick up a smaller pair of snub nose vise grips or something while I'm at the store.

John_AZ

SENSOR bracket bolt.

Use a metric 6 side head bolt with the same length now used. Should be 8 x 25 and same thread/pitch-8.8. Anti-seize the bolt threads. Use anti-seize on the reference sensor as well.




You might try a socket extractor of the hex head. The bolt is corroded in the block. The bolt on the drivers side is impossible to get a tool on with enough force.

If you cannot get the bolt out. DO NOT smash the sensor bracket in anger. Rock the sensor bracket and gap the sensors per Clarks. Leave the bolt in and move on.

GL
John

Player0

Hi, yeah I've gotten the bolt out, the problem is the sensor. I have vice grips on the sensor now, and I have vice grips on those vice grips to extend the handle so i can really pull on it. After an overnight of soaking in PB blaster, I still can't pull the sensor out.

Is there anything in this area that can be easily removed to make more room to work on this part?

I wonder if I should call it quits and just pull the whole sensor bracket. It sounds like a real pain to regap the bracket, so I've been avoiding it.

Any other tips to pulling one of these sensors? Or do I just need to do some weight training?

John_AZ

STOP.

Any force on the reference sensor will cause it to break in half. When this happens, the lower half stays in the sensor bracket and you have no other choice but to smash the bracket off.

In the first photo, I had a sensor corroded to the bracket. I soaked it in penetrating oil, Kroil, oven cleaner, lime away and any other chemical I could find. It did not budge. I cut the sensor bracket to free the sensor. See photo.

You have to be gentle, wiggle a little. If you twist too much you will cause the thin wires in the sensor to break.

Good luck. If you ruin the sensor, get the BMW '88 535i interchange with steel cap bottom. A lot cheaper than OEM Porsche. If you want OEM, AutohausAZ has a sale on now.

To get more room, pull the intake manifold off. This will give you the room and the time to do other fixups like the AOS seals, heater control valve, vac lines, clean the ICV ++++++++

GL
John

Joe Jackson

The cylinder on the stock part acts to limit the compression on the sensor when tightening it down. I would not replace the stock shoulder bolt with a normal bolt.

If you still need one, I have an extra in my box of random hardware. PM me if you are interested.

John_AZ

The bolt I was referring to was the sensor bracket bolt , not the bolt that holds the sensor in the bracket.
I misunderstood what part PlayerO was referring to.

Joe Jackson is correct.

John

Player0

I ordered a bunch of stuff today since I'll be pulling the intake after all. Thanks for the tips on the AOS, heater control valve, ICV, etc. I'm taking your good advice and will service/replace all of thsoe, vacuum lines, anything else I find under there.

Quick question though, I haven't found any particulars on cleaning the ICV valve. Is throttle body cleaner enough or does it need something else?

One of the symptoms I had when the car was running was that it threatened to stall right after start up. The car was in dire need of a tune up and the coil was pretty shot. But after reading on the ICV, it's possible it was also causing trouble.

Is there any way to be sure whether or not it needs to be replaced?

Player0

More details on the symptoms when it was running:

Start the car (summer, so quite warm out), engine fine but then the idle would slowly come down, until it stuttered and I needed to give it a little gas. After the engine warmed up, this goes away.

The other running issue I had was high speed miss. At full open throttle, 1 out of 6 times at 5000+ RPMs the engine would 'miss' a bit.

Like I said, coil is not great, and a tuneup was needed (last one was 11 years ago).

John_AZ

ICV/ISV tuneup:

http://www.texasblake.com/porsche/tech/icv.html

More detail:
http://forums.pelicanparts.com/porsc...dle-valve.html

The "miss" sounds like a bad coil wire, bad wires, bad plug---use cheap copper NGK or Bosch no platinum. Could be a intermittent bad/dirty ground. Coil--usually not.

GL
John



Gl
John

Player0

Hey guys,

I have the intake manifold off and all sorts of room now. The sensors will still not budge even after days and days of tapping, twisting, soaking in PB blaster. For whatever reason, they are completely locked to the sensor bracket from underneath.

So I've been trying to remove the sensor bracket itself. The top hex bolt came off, but the bottom 6mm hex head bolt on the bottom (sort of under the reference sensor) also seems to be quite frozen. I've been working at it for days but there's just no room between it and the firewall to really get any torque on it.

I ordered a snap-on 1/4" 6mm ball hex socket online and I gave that a go, but the ball just pushes back up and out of the hex head when any amount of force is applied. The allen head just feels so shallow for some reason.

I ordered a non-ball hex socket, also in 1/4" as anything large won't work right. I'll get it next week but I don't have much hope in it working. Even if the socket stays inside the bolt, i have about an inch on the socket to actually apply the force.

I'm about to give up, put this thing on a flat bed and let someone else deal with it. I'm just out of tool ideas for getting this thing out. Before I drop $1000 on this problem, any tips or advice? Are there any tools that could be particularly useful here? Someone has had to go through this before.

Thanks!

John_AZ

Well now you have time to read the "What I had to do" thread.

http://forums.pelicanparts.com/porsc...che-gurus.html

Smash the reference sensor bracket and get another may be your only choice.

GL
John

John_AZ

Here are some of the WYAIT (while you are in there) repairs while you have the intake off on your '86 turbo
.
1. Replace the AOS seals
2. Replace any old vacuum line, hose, boot.
3. Replace any crimp clamp on a hose with a fuel injection clamp or a non perforated screw clamp.
4. Replace the heater control valve and small "J" hose to engine.
5. Clean all connectors and grounds.
6. Use CRC Fuel injection and throttle body cleaner.
7. Rebuild the Throttle body with a $20 kit from www.arnnworx.com
8. Send the injectors to be cleaned and balanced. ie www.witchhunter.com or similiar.
9. More...sure

GL
John

Player0

Smash it? Gladly.