The crankshaft position sensor....

I recently purchased the Durametric tool. Yesterday while learning how to use the instrument and looking at the various areas of the car on which it gives information, I got the following Fault Code: P0335 Crankshaft Sensor. Can anyone explain what this means? Do I have an impending problem? There is no CEL or other indication of a problem.The car starts and runs fine with absolutely no issues. Car is 2007 Boxster S with manual and 22,000 miles.Any thoughts/ideas appreciated.

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oldhoo07s
I recently purchased the Durametric tool. Yesterday while learning how to use the instrument and looking at the various areas of the car on which it gives information, I got the following Fault Code: P0335 Crankshaft Sensor. Can anyone explain what this means? Do I have an impending problem? There is no CEL or other indication of a problem.The car starts and runs fine with absolutely no issues. Car is 2007 Boxster S with manual and 22,000 miles.Any thoughts/ideas appreciated.

burned out?

In some cases even though the DTCs can be read and return non zero numbers if the number of DTCs is zero and the MIL status is off the codes are not real, but left over or stale codes. The number of DTCs and the MIL status are returned in a separate query to the ECU.

If the code is real -- and generally without any other symptoms/behavior the recommendation would be to clear the error code and drive the car and see if the code comes back or any symptoms appear -- it could be a going bad sensor, or a poor electrical connection (surface corrosion interfering with the signal), a weak battery or possibly even the first signs of a bad starter.

If you feel up to it you could find the sensor -- from under the car I think would be the best place to start but you'll find out -- and disconnect then reconnect the sensor connection -- do this with care! -- and see if this doesn't help. (Do you have you washed the engine?)

Crankshaft position sensor (CPS) failures are rare so my advice would be as I mentioned above: clear the code; drive the car; always though at the first or any sign of real trouble shut off the engine first and ask questions later.

However, you are certainly free to consult with your trusted Porsche tech and get his input.

error, but AFAIK the crankshaft position sensor function is not affected by any IMS wobble. Theoretically misfires could arise as the IMS wobbles but if so this is the CPS doing its job. The ECU determines by the CPS signal the flywheel is not accelerating as expected during the cylinder's power stroke and this lack of acceleration if bad enough and if it occurs over a span of time is a misfire.

However a wobbling CPS value can be caused by a 2-part flywheel deteriorating. Ask me how i know.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com



Edited 1 time(s). Last edit at 08/18/2013 08:15AM by grant. (view changes)

every tab or tooth on the ring of tabs/teeth around the FW -- there is a missing tab or two which is used to note where the #1 cylinder is in time -- and these signals are used by the DME to detect misfires. It measures the time between each tab/tooth and in doing so measures the presence of (or absence of) the acceleration each cylinder's power stroke contributes to the FW's rotational speed. Any deviation from what is considered acceptable and for too long a period of time is classified as a misfire.

nothing driven by the IMS.

Grant

gee-lenahan-at-gee-mail-dot-com

affected by a wobbly IMS and IMSB and this can (possibly) show up as a misfire. That was what I was saying, or trying to say.

My impression though is by the time the IMS/IMSB is bad enough to cause misfires the engine is just about if not already at some terminal condition and the noise and and in the more advanced cases even the smoke and oil/coolant pouring from the engine makes the CEL and any misfire codes that may be associated with it kind of immaterial.

Hey MarcW, thanks for the input. Pretty sure the CEL bulb is good. I will clear the code, drive the car and see what happens.

When our crankshaft sensor went, there was also no CEL.

The problem showed up only periodically at first...the car would start fine in the AM. We would run it for about 10 minutes (to get coffee), stop, and would not restart. After waiting for about 30 minutes, it would restart fine and there would not be any problems. As the restarting problem was very sporatic, we did not give it much thought. Actually drove it to NYC!

We ran the car this way for a few weeks, then one day, after having driven it for about 5 minutes, it cut out when making a slow left turn. Could not get it restarted after 30 minutes, but it DID restart after letting it sit for 2 hours while waiting for a tow truck to show up.

Drove it home. The local mechanic found the crankshaft position sensor error code, changed the sensor, and it has been fine since.

So unless you want to live with that little time bomb, we would suggest getting the sensor replaced :-)



Edited 3 time(s). Last edit at 08/12/2013 01:18PM by RainyDayGarage. (view changes)

The crankshaft position sensor is a simple halls-effect sensor which may give false warnings every so often due to dirt/oil buildup and also at the connector where corrosion may also produce an error.
But, sometimes they do fail. When they start to go the general symptoms are that the car won't restart when hot and/or the car will cut off for no reason leaving you power-less.
I just replace one last week on a '99 Boxster.
Try disconnecting the sensor and spraying electrical cleaner on the connector and the plug.
Clear the code. If it come back it could mean that the sensor is on it's final leg.
They're not cheap either.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

Pedro, can you tell me where the sensor is located and the best way to get to it? Also, is it something I can purchase from a parts source and replace (limited mechanical ability) myself?

... is located on the right side of the engine, next to the bellhousing, just in front of the AOS.
You need to remove the right rear tire/wheel to see it and the best way to remove, clean or replace is from underneath.
It's not terribly difficult to do, but the part is several hundred dollars, so you need to be sure that it is bad otherwise ...
You'll need to disconnect it first and free the wire. Then just one allenhead bolt holds it in place. But to get to that bolt you'll need a really long extension (18" minimum) with the allen tip (IIRC it's a 4 mm hex)
I don't know of a third party who sells these. The ones I've replaced are OEM, purchased from Porsche directly.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

sensor require consideration?

MarcW and Pedro, thanks for the advise. FWIW when I got home from work yesterday I cleared the P0335 fault code and went for a 20-minute ride and the code did not come back. So, I will drive it and see what happens from here. If the code comes back I guess I will be proactive & take it to the dealer since the part is OEM Porsche. If the fault code comes back but the car shows no problems, what would be a good plan of action?

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oldhoo07s
MarcW and Pedro, thanks for the advise. FWIW when I got home from work yesterday I cleared the P0335 fault code and went for a 20-minute ride and the code did not come back. So, I will drive it and see what happens from here. If the code comes back I guess I will be proactive & take it to the dealer since the part is OEM Porsche. If the fault code comes back but the car shows no problems, what would be a good plan of action?

in this case the CPS.

The CPS is not super expensive nor is it hard for a DIY'er to replace. It is throwing parts at a symptom but sometimes absent access to more test equipment and the expertise to make the most of it -- expensive -- this is not a bad thing.

This is after I assume you have found the sensor and carefully disconnected then reconnected it at the wiring harness to remove any surface corrosion that might be interfering with the sensor signal to the DME. I "fixed" a camshaft position sensor this way on my '96 Mustang GT. I finally took the time to locate and disconnect then connect the connector and a persistent camshaft position sensor error -- never accompanied with any other engine symptoms -- never came back.

While in my experience CPS failures are rare one can't ignore the error code and after eliminating the possibility of surface corrosion at the connector if the error code persists your car it would appear has one of the rare (but not unknown) CPS failures.

There is no adjustability when installing.
The sensor's depth is preset by the base where it mounts.
Obviously the base needs to be cleaned before installation.
What I've seen is that when they go bad they generally start failing intermittently and it's always been an electrical issue.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

The crankshaft position sensor was probably my most frustrating Boxster problem. I'd drive to the store and it wouldn't start when I got out. I'd wait 30 minutes and it would fire right up. It got to the point where I'd be driving on the highway at 65 mph and the engine dies. Flat bedded the car home and it started right up.

Thanks to the diagnostic help here (or perhaps PPB and other forums, it was a simple DIY and the part was less than $100 and no problem since!

Here is some info on the repair: [forums.pelicanparts.com]

Thanks BoxsterBob for the input. The link info was what I wanted to see. Just curious as to where you found the part for approx $100.00. I see on Pelican Parts the Porsche OEM part for $238.00.