Chuck Henry

There are two similar sensors near the timing window on the back/left side of the engine. One of the plugs crumbled when I was pulling the intake manifold and I'm hunting for what it's called so I can order another. I would guess it's a crankshaft position sensor but don't know for sure.

Also, the old sensor only came out about 1/2" and I can't get it any further. Before I apply even more force, there isn't a trick to getting it out.

Also have a broken temperature valve and a couple other things but I think I know what I'm ordering there. Thanks in advance!

mytrplseven

The two sensors are the "Reference" sensor and the "speed" sensor. If one is being difficult coming out, it's likely due to a bit of contaminant that's built up on the smooth shaft of the sensor. I'd suggest spraying some nut buster into the shaft area and moving the sensor up and down a few times before trying to pull it out. Clark's Garage has info on replacment and adjustment of the clearance of these sensors. Don't mix them up.

Chuck Henry

Fantastic. Thank you.

harveyf

Further info. The 2 sensors are the same, they have the same part number. The retail price of an OEM sensor is around $200. I see that Paragon Products has 2 listings, one for $56 and one for $84. You might call them to discuss the differences. I know that there is a sensor produced for BMW(?) which is identical except the cord is longer than Porsche. At least one of those at Paragon is probably the BMW sensor. I have bought and used the sensor with the longer cord and it works fine. Identical at both ends to the Porsche OEM sensor.

I'm not sure why but the connector on the sensor end tends to fail versus the one on the engine wiring harness. If you are just trying to fix the crumbling connector, Roger at 928srus sells a replacement plug kit that I used on my 928 (and that will work for a 944). The kits are cheap, buy 3 as you will probably screw the first one up trying to learn how to crimp the connectors, etc.

The standard low tech test for the sensor working is to be able to see a "tach bounce" when cranking the car. There are also resistance and voltage checks that require a decent meter and a shop manual.

Do yourself a favor and get the 944 shop manual either off the internet or available for about $20 on a DVD. You will need to refer to the pictures in the shop manual that tell you which sensor goes to where and how the pins are wired. One sensor generates a once a crank revolution voltage spike and the other generates a spike every time a gear tooth on the flywheel passes by. Get them switched and your car won't start.

I agree with mytrplseven to douse the stuck one with penetrant before you pull too hard and break it. You can rotate it as you pull to loosen it up. Also agree that Clarks Garage website is a fantastic resource for maintaining your car.

Good luck.

Chuck Henry

I appreciate the additional info. I've got the factory manual and also have printed out most of the clark's garage write-ups that I stuck in a folder in the garage. From my Audi days I was fairly certain that it was a crank sensor I just couldn't find it in the manual. Still a learning curve on all this stuff for me. Now I'm trying to figure out what the vacuum relay thing is that has 3 hoses running into it. The plug into it is damaged and I the blades were bent. Hopefully it survived, but I wanted to know what it was!

Always such a learning curve on a new car, especially being my first Porsche!

harveyf

We're here to help! It would be good to add a signature line with the year and model car you own.

Chuck Henry

Ok, I hate seeming like a total newb, but where do I set up a signature? I wasn't able to find it looking in the User CP.

BReif61

Need to be a paying member to have a signature, Chuck.

Chuck Henry

That would explain it then! At least I wasn't being completely stupid... this time.

harveyf

Hey, sorry, led you right into that one. Rennlist has been a good investment for me. Become a member, you won't regret it.

mytrplseven

It would be good to have a picture of the "vacuum thingy" you referred to so we can lead you in the right direction.

Chuck Henry

I'll take one tonight of "the thingy". ;-)

Chuck Henry

Here it is, I guess it's called a timing valve for charging pressure. As you can see, my plug is melted. Anyone know where I could get a replacement?

Will Feather

This would be your cycling valve.

Not sure where to locate the connector.