996 Cam Deviation values on PIWIS V3

Hi all, I am doing some maintenance on my 996 C4S and wanted to check if my car had any camshaft deviation. I bought a laptop with PIWIS 3 and 4 last year so that I could check the values. However, When I select the " Camshaft Position 1/2 deviation" it comes up with values I don't understand. Also the values don't change even when the car is underload or revved at idle, the only way to get "new" values is to re-scan the car. The units are in "degrees" KW which I don't get, unless the KW part is irrelevant and it just means degree, but I'm not sure. Even so the values I am getting don't correspond to other values that I have searched for online, I have read that the camshaft deviation should be between +-6 degrees. But my values range from 0.06 to 0.17 on position 1 and 0.00 and 0.13 on position 2. Below I have attached some photos of my PIWIS V3, if anyone can shed some light on what these values mean it would be much appreciated. Many Thanks.

The KW there is not kilowatts, it is almost certainly Kurbelwelle, so crankshaft degrees. That part is normal on the German PIWIS wording. The other thing is I don’t think that screen is showing the same cam deviation figure people normally mean when they talk about values being within around +/- 6 degrees. Your numbers are tiny, so on their own they don’t look concerning at all. More likely you are just looking at a static/sampled value rather than the proper live cam timing or adaptation data. I’d go hunting for the actual inlet cam angles / adaptation values on live data or the logger rather than reading too much into those screenshots. From what you’ve posted, nothing there screams timing issue. Camshaft Position 1 Deviation of -8.97 Car in question: 1999 C4, M96.02, 41k miles (had it since 20k miles), original/stock IMS bearing Alright, so I stumbled on some posts regarding durametric readouts for camshaft deviation to check into the health of the IMS. I remembered I logged a bunch of real-time parameters back in 2012 just t... www.renntech.org

Take your readings only after a good long drive at varying engine speeds & loads. The engine should be hot when you view the data. The reading will be an average over the duration of running time and is stored infinitly unless the battery is disconnnected which will wipe the history.

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Why do you say that?

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the Kurbelwelle value is operating within a normal 'near zero' range

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I thought you meant the +-6 angle often quoted to gauge chain pad wear is some different measurement. I agree the OPs camshaft deviation figures are normal. They fluctuate even at idle on my car so they are not static as they come out of PIWIS 3. As it's a deviation I don't know why/if it should change in magnitude under load/revs. There's a separate measurement in PIWIS to get the angles themselves. I've been meaning to plot the angles on my car while driving, to verify the variocam+ system works as intended.

I went back out in the car and got some more results. The camshaft deviation values didn't change, when the car was fully hot the bank 1 deviation was 0.17 KW and bank 2 was 0.00. I also added Actual Angle for Inlet camshaft bank 1 and 2, again I couldn't make any sense of these values. I also did setpoint angle for inlet camshaft and Spec angle for inlet camshaft with no luck. I also recorded a video of the car with these values while driving and have attached it.

It is very hard to tell what's going on but just from the discrepancy between the engine noise and the rpm shown on screen there seems to be significant lag. And again deviation is not meant to stay the same. Have you tried a different VM image and assigning more RAM to the VM?