MY99 Boxster crank position sensor

[Randy_K]

Has anyone on here replaced there crank position sensor themselves? I have one coming and want to install it this weekend. But I am unable to find any DIY info on how. I have seen pictures of where it is located on Pelican. But still hard for me to tell. Since the picture of the postion of it is while the engine is on an engine stand.

Can I get at it from the top of the engine compartment? Do I have to go at it from the bottom? Etc... What parts need to be removed to get to it.

Pic's would be helpful. And what is you recommendation for the accomplishment beer when done? LOL

Thanks for your help gentleman. Randy

[Loren]

From the rear of the Boxster you are facing the flywheel/clutch housing - about half way up the bell housing on the right side.

[Randy_K]

From the rear of the Boxster you are facing the flywheel/clutch housing - about half way up the bell housing on the right side.

Thanks Loren, Someone on Pelicans site, posted this pic for me. I hope it is helpful for the next guy doing this.

[Randy_K]

Successfully replaced the CPS Saturday morning with help from a fried with way more tools, smaller hands and younger. LOL It only took about 1.25 hours to do. Actually, the hardest part was getting the ring clip to release the keeps the wire from flopping around between the sensor and the other end/plug to the wiring. Working by blind there.

I'm attaching a pic that shows the old sensor. It's not a great pic. There are grooves cut in it, like you could make with a small jewelers file. Couldn't get the flash to work on my camera. JFP suggested it may be an aftermarket flywheel causing them with a bent shutter element? Since I don't know when the flywheel was replaced, if ever? I know in the old days. It was typical to replace that when the clutch was replaced along with the pressure plate. I'd like a better understanding how these things work. The grooves that are worn in it, to me, look like electrical strike marks. Not mechanical. But like I said. I have now idea how this thing does what it does.

The starter makes a squealing noise about 1 out of ten starts after the key is released. The Porsche shop I take it to here. Said that was a bushing in the starter that commonly wears and not to worry about it. Don't know if that could be the issue with the sensor or not?

Randy

Edited March 1, 2011 by Randy_K

[JFP in PA]

The CPS is a simple “Hall Effect” sensor; it is located near a shutter wheel (on the back of the flywheel) that creates a signal when the shutter passes near the sensor. This is also the way the old “electronic” distributors worked when cars still actually had distributors (God, am I dating myself).

The following picture shows the shutter assembly on the rear of the flywheel, and you will note the bent shutter prong near the center. As the shutter is pretty close to the sensor, there is not a lot of room. One individual actually had a fastener come loose inside the bell housing and whack the sensor as well.

Your starter noise is very common, pull it and clean the Bendix drive, then lubricate it with a dry DuPont Teflon spray lube and you will be back in business.

Edited March 1, 2011 by JFP in PA

[Randy_K]

Thanks JFP. The starter sounds like a simple fix. As far as dating yourself. At 58, I'm not a "spring chicken". If that saying doesn't date me. I don't know what will?

Edited March 1, 2011 by Randy_K

[JFP in PA]

God, to be 58 again.......................

[harryrcb]

God, to be 58 again.......................

Well I got him beat, I just turned 46 last month, errrr I mean 64 , I think , oh darn I can't remember.

speaking of not remebering JFP , did he say he had a light weight flywheel? cause the stock one has solid nodes for the sensor and can't bend, but I'm sure you know that.

Edited March 2, 2011 by harryrcb

[Randy_K]

Well I got him beat, I just turned 46 last month, errrr I mean 64 , I think , oh darn I can't remember. speaking of not remembering JFP , did he say he had a light weight flywheel? cause the stock one has solid nodes for the sensor and can't bend, but I'm sure you know that.

Harry, On Pelican's site, JFP said that the car that flywheel came off of. Had the same or similar marks on the sensor and that is an after market lightweight flywheel. I have no idea what this thing has in it.(mine?) But I now understand, (kinda) It creates, in my opinion, an electromagnetic field/electrical signal because of it, that sends a signal upstream.

I accidentally set an ink pen, with the top on it and the pocket holder attached next to the sensor and it stuck to it.

What I'm not sure of. What part of this thing sits close to the flywheel. Given that it has a large plastic surround, around the metal rod and it is perfect.

It's not my intention to drag this thread out. But I think how and why something works is important. It leads to why something doesn't. I love learning!!!

Randy

Edited March 2, 2011 by Randy_K

[JFP in PA]

Well I got him beat, I just turned 46 last month, errrr I mean 64 , I think , oh darn I can't remember.

speaking of not remebering JFP , did he say he had a light weight flywheel? cause the stock one has solid nodes for the sensor and can't bend, but I'm sure you know that.

Is this where I ask if I have posted yet?

Yes, I am aware that the photo is a lightweight wheel, which is why I originally asked if he had the factory or an aftermarket flywheel. The stock wheel can still have problems in this area as well if something comes adrift inside the bell housing, like a bolt head or piece of clutch facing, and starts banging around and buggering up the factory shutter elements. There is very little room between the sensor and the shutter, otherwise the sensor would not generate a signal; and if anything solid tries to get between the sensor and the flywheel, or causes a burr to develop on an element, usually leads to needing at least a new sensor.

[harryrcb]

Is this where I ask if I have posted yet?

You got me there.

[harryrcb]

Well I got him beat, I just turned 46 last month, errrr I mean 64 , I think , oh darn I can't remember. speaking of not remembering JFP , did he say he had a light weight flywheel? cause the stock one has solid nodes for the sensor and can't bend, but I'm sure you know that.

Harry, On Pelican's site, JFP said that the car that flywheel came off of. Had the same or similar marks on the sensor and that is an after market lightweight flywheel. I have no idea what this thing has in it.(mine?) But I now understand, (kinda) It creates, in my opinion, an electromagnetic field/electrical signal because of it, that sends a signal upstream.

I accidentally set an ink pen, with the top on it and the pocket holder attached next to the sensor and it stuck to it.

What I'm not sure of. What part of this thing sits close to the flywheel. Given that it has a large plastic surround, around the metal rod and it is perfect.

It's not my intention to drag this thread out. But I think how and why something works is important. It leads to why something doesn't. I love learning!!!

Randy

Like JFP said, the center of the sensor (shiny part) is extremely close to the flywheel in order to trigger the sensor, but if that shiny part in the center is in good condition then thats not your problem.

[Loren]

[williampeyton]

Hello I have a 1997 BOXSTER 2.5 ENGINE manufactered for U.S.

Okay just read the post about the camshaft positioning sensor, when I scanned my code it came out to be; CODE: P3151 CAMSHAFT POSITIONING SENSOR BANK 1 TO BANK 1. Questions are these, I know there is two camshaft position sensors, which one did you replace and how did you know to replace that one and not the other one. Will i have to drop the engine from the transmission to replace the one you replaced in the photo or can i do it while the engine and everything else is still in place. I have been driving my car like that for a month and today my check engine light started flashing when i was driving and I made the vehicle accelerate hard and fast when comeing off the off ramp to get my place in traffic. The engine did not make any weird noise and the idle did not flectuate and was at its normal idle speed 900rpm. The check engine light only flashed for 15 seconds and then stopped, i drove back home immediatly and the check engine light did not do it again even at the top speed of 80 mph or 128 kph. Please help me i have the tools and the garage and refuse to pay money on a job i know i can do myself.

[Randy_K]

Sorry William. I'm afraid I can't help you with your question. I replaced the Crankshaft position sensor. Not the Camshaft sensor. But I have seen threads on the site with the info you need.

Best of luck, Randy

[JFP in PA]

Hello I have a 1997 BOXSTER 2.5 ENGINE manufactered for U.S.

Okay just read the post about the camshaft positioning sensor, when I scanned my code it came out to be; CODE: P3151 CAMSHAFT POSITIONING SENSOR BANK 1 TO BANK 1. Questions are these, I know there is two camshaft position sensors, which one did you replace and how did you know to replace that one and not the other one. Will i have to drop the engine from the transmission to replace the one you replaced in the photo or can i do it while the engine and everything else is still in place. I have been driving my car like that for a month and today my check engine light started flashing when i was driving and I made the vehicle accelerate hard and fast when comeing off the off ramp to get my place in traffic. The engine did not make any weird noise and the idle did not flectuate and was at its normal idle speed 900rpm. The check engine light only flashed for 15 seconds and then stopped, i drove back home immediatly and the check engine light did not do it again even at the top speed of 80 mph or 128 kph. Please help me i have the tools and the garage and refuse to pay money on a job i know i can do myself.

The cam position sensors (one in each cam cover) are very simple to replace. They are held into the cam cover by a bolt, so all you need to do is unplug the suspect unit, undo the fastener and swap it out. This has been covered here and on other websites, so a search should generate plenty of info. The Bentley manual also covers it, with a photo as well.

[bar10dah]

Sheesh! Randy_K, how in the heck did you get at that crank position sensor?! I'm having a tough time getting my hands/tools into that tight spot. Even with the passenger rear wheel removed...

[flyingpenguin]

Sorry for reviving this thread, but am trying to systematically eliminate possible causes why rebuilt 2.5 engine is not starting, even though it is cranking (so can eliminate immobilizer issues).

Fuel relay may also be the culprit, but jumping it gives me the required 3.5 bar fuel pressure on the rail.

Found a generic thread (for a MINI) stating that pins 1 and 2 (not sure what pin 3 is for) on crank position sensor should read 200 - 500 ohms and 0.2 - 2.0 V AC (when installed and engine cranking). My CPS reads 932 ohm and 2.2 V AC. Out to try a new CPS tomorrow but any insight would be appreciated.

Cheers Joost

[flyingpenguin]

Problem solved!

Turns out the wiring connector for the HAL sensor (cam position) is the same form factor as the one for the Crank Position Sensor. Just the color differs.

Of course mine were switched out after complete engine reassembly, so made sure grey is on grey and black on black,

Phew..

[RFM]

Glad it is resolved, pay attention to the wiring nex time, the colours, and Hal sensors have 3 wires, Inductive sensors have only 2 wires. Are there no error codes appeared?

[ed.w]

hi Randy

My Boxster S Yr2000 just got OBD code#P0336. Isn't it indicate I need to have the Crankshaft Speed Sensor changed ?

thanks.

Has anyone on here replaced there crank position sensor themselves? I have one coming and want to install it this weekend. But I am unable to find any DIY info on how. I have seen pictures of where it is located on Pelican. But still hard for me to tell. Since the picture of the postion of it is while the engine is on an engine stand. Can I get at it from the top of the engine compartment? Do I have to go at it from the bottom? Etc... What parts need to be removed to get to it. Pic's would be helpful. And what is you recommendation for the accomplishment beer when done? LOLThanks for your help gentleman. Randy

[JFP in PA]

hi Randy

My Boxster S Yr2000 just got OBD code#P0336. Isn't it indicate I need to have the Crankshaft Speed Sensor changed ?

thanks.

Has anyone on here replaced there crank position sensor themselves? I have one coming and want to install it this weekend. But I am unable to find any DIY info on how. I have seen pictures of where it is located on Pelican. But still hard for me to tell. Since the picture of the postion of it is while the engine is on an engine stand. Can I get at it from the top of the engine compartment? Do I have to go at it from the bottom? Etc... What parts need to be removed to get to it. Pic's would be helpful. And what is you recommendation for the accomplishment beer when done? LOLThanks for your help gentleman. Randy

 

 

P0336 indicates an open circuit for the crank position sensor, so yes, you need a new one.

[ed.w]

Thank you, JFP.