Success at last! Thanks to everyone who provided a suggestion.

Here are my notes for future reference in case they can ever help anyone.

Today i tried Bertranddaoust's approach and that did the trick.
I went to HD and got the following:

Screw - M10 x1.5x 70 (threads on entire length) - $1.80
Nut 10x1.5 - $.96
Already had a washer to fit
1/2" Copper coupling $.55

I also got an M8 x 1.25 but that's almost the exact size of the magnet so couldn't get a grip.

The plastic was spinning inside the cylinder so tapping it was a bit hard and it took more than a few tries to actually get the screw to bite into the remaining plastic (drill with a long extension to drill as straight as possible). Once it did I was in business. Stubby 17MM wrench a bunch of turns on the nut and it finally came up. I think once i got past the rubber o-ring it just slid right out.

1st pic is a shot of the whole setup once the sensor was out

2nd pic a shot of how I spent more than several hours each of the last 5 nights so I could get access right above the sensor

3rd pic is what the sensor cynlinder looks like now, there's some scratching at the top from picking at it, but I think it's still in good shape

4th pic, I mentioned i tried to drill to try and get metal but couldn't punch through... well turns out I did reach the end of the sensor and a good thing the metal was too hard. If you're going to try this approach you need to sink into the remaining plastic once you remove the magnet.

This was definitely an exercise in patience, and to anyone that reads this in the future, if you're not a member, seriously consider joining. This forum is hands down the best 928 purchase I've made. Couldn't of done this without all the help on here, thanks again guys.

Time to celebrate the victory here's hoping i don't have to do this for another 20 years (and that the anti-seize i plan to use makes it far easier)

 

Well done Oded - you are becoming a savvy 928 owner.

 

kaelix,
Good for you. I've been following, and was worried you were going to damage something and complicate matters. One of the things I've learned on the 928 is that access is key when removing/installing old things that have been there a long time. Even if it means a big tear down, it ALWAYS makes things easier in the end.

 

Happy ending!

I learned with the time that working on a 928 is a labour of patience and time.
Very rewarding when you get over something like this.

Nice job.

 

Great job!

 

Hello evryone,
I am getting ready to replace the CPS as I was stranded on the side of the road in my 1987 928 S4, the car started after cooling off about 45 minutes. I appreciate very much all the info so far, but I have two more issues.
1. I still have the throttle cable pully in the way, how do you remove the pully?
2. how do you get the other end ob the CPS unplugged, it is very hard to reach and don,t want to break anything?

 

It's my understanding that if the CPS has gone bad the car won't even start so if letting the car cool got you going again, doesn't sound like a CPS issue. I'll defer to someone more experienced.

If you want to replace the CPS anyways make it easier for yourself by taking off everything that's in the way, fuel regulator, fuel damper, fuel lines, and the horizontal bracket that's under the cable/wheel guide.

Good idea to check the condition of your fuel lines while you're back there, and more than likely replace them.

The horizontal bracket is held on by two bolts on either side. I've circled one approx location in blue in the pic below, the other bolt is in a similar position on the other side. These are ground points as well and should be cleaned, you might not be able to see them until the fuel related components come out.

Once you remove the horizontal bracket the throttle cable has slack and you can move it around or out of the way.

The CPS connector joins another connector on a vertical bracket (that's attached to the horizontal bracket) that has a "cutout" to match the connector (and on an early 87 like mine there is a fuel line around there too). The CPS wire runs from the vertical bracket connection to the actual sensor, you can see both ends in my pic but I can't find a pic I took of the vertical bracket.

Hope that helps

 

There are many instances of CPS failing when hot, working again when cold, etc. etc.

 

Good to know!

 

I hope that the CPS will solve my problem. I was lucky and was able to pull the sensor end out with some WD40 and some twisting, however the connector end started to crumble and it is stuck.
I have two questions:
1. Does the connector just pull out at the connection or is there a trick to separating the connector ends?
2. The big pulley in the above picture is in the way and can not reach the connection, do I need to remove the big pulley or not?
Thanks everyone for the info I would have had a tough time without all the usefull info that you have provided, special thanks to "Kaelix" of Dallas for the info and very helpful pictures.

 

Glad to hear it came out easily.

The wire for my connector is/was routed on the other side, i.e. not under the pulley/guide wheel. If i remember correctly, the connector has a thin piece of "wire" that goes almost all the way around it. I believe this secures both connectors together. If you remove that wire you should be able to disconnect by just pulling them apart.

Since you're going to get a new sensor you don't have to route under the guide wheel, so if it's easier to cut the cable close to the connector and pull it out from the sensor end, that's the approach I would take. When you install the new one route it a different way, as long as it's doesn't get in the way of anything i don't think the routing matters.

I'm sure someone will chime in if i'm wrong

 

done with the CPS replacement, had a tough time with putting the connector together because of space limitations and also part of the old connector broke inside the connection and had to dig it out without damaging the part. started with the first crank, but it seems like I may have another issue. It is hard to start when it runs for about 10 minutes. I am thinking fuel filter, fuel pump relay, or fuel pump.
Thanks for your help "kaelix"

 

pull the vacuum lines off of both dampers and the fuel pressure regulator,
smell for fuel,
if you smell any gas then the part should be replaced

, if you dont smell gas then the next thing to do is check the fuel pressure while sitting,
its possible the check valve in the fuel pump is bad,
or the fuel pressure regulator is bad,
or the injectors are leaking.

Before replacing any parts,
try adding a bottle of techron to the fuel and about 6 oz of MMO to the fuel.
do lots of short drives so the chemicals have time to work,
about 20 miles then shut off the engine and let it sit till cool

 

appreciate your response "Mrmerlin", got a chance to drive the car over the weekend and switched the fuel pump relay with the horn relay, no change, the car runs good for 10 to 15 minutes and as soon as the electric fan kicks on the fuel pump relay clicks and the car dies. I noticed there is another thread just posted on tonight "engine cut out" if you would please respond on that thread, Thanks

 

Hi there

thought i'd try to revive this thread as i'm running out of ideas. i've Dremel'd out the top and the plastic 1/4" down but can't pull the magnet out. Any ideas what i should do now? i'm wary of dremeling too much and damaging the housing. soldering iron didn't work too well for me.

I'm in underground car park in my building so can go in from the bottom. also couldn't get the throttle wheel out the way as seems to have metal fuel lines welded to it that go right down into the engine bay. so access is really tight too.

Here's couple pics of where i'm at.




Magnet of the CPS<br/>