986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - Engine noise diagnose assistance - Possible vario cam actuator/pad/chain issue?

bg305 · 05-12-2021, 12:40 PM

First of all thank you to everyone taking the time to read and reply, I appreciate your thoughts.

Background: 2001 S, 53k miles, Fabspeed exhaust, tune (I believe done by fabspeed, it happened 2 owners ago). The tune is possibly ROW, but I do not know for sure. The reason this believed is because it does not have the normal amount of emissions monitors. I have owned it for a bit more than a year and 1/2 and replaced the AOS when i got it. So far as I know no other major work has been done (original IMS assumed, no chain guide replacements, etc). I noticed a small amount of brown plastic in the filter last oil change from the vario cam pads. It was my second oil change since owning the car and the first I did not see any plastic, but I do not know how long the oil was in it that time. Other then that the car was running like a champ.

I have been monitoring my camshaft deviations since I found the plastic (this past fall) and they seem to sit around:
Camshaft 1: -0.74 (this does increase to 1.60 or a bit more as it warms up and then goes back down)
Camshaft 2: -9.27

Now the problem / question:
I was out for a nice drive a couple of weeks ago, enjoying a corner probably in the 4-5k rpm range in 2nd, some g-forces but nothing crazy, let's call it 60% of what the car could do in that corner. I noticed mid corner the engine seem to take on a different sound. The intoxicating whale sounded more like a Subaru (Not picking on flat 4's, that is just the best way I can think to describe it).

I drove it home 8-9 miles cautiously. It is possible it had lost some power, but given how gingerly/cautiously I was driving it, it is more likely just my perception. If there was a change it was not big.

I finally got out today (work has been insane for a bit), put it in service mode and checked the intake for obvious leaks and the exhaust (just a quick check, nothing detailed, the car is still on the ground). So while I can't discount a leak in the intake / exhaust, I do not see any evidence to point me in that direction.

My concern of course is the vario cam actuator / guides and chain. I am far from an expert on these systems but am hoping that this video I took will help show the data in a way that someone here might see something if there is an issue

I had planned to try to get through the season and then replace the vario cam pads along with a pro-active ims / clutch /etc. But I think i might have to do that a bit sooner possibly.

Note: at the beginning of the video I say crank angle, but meant to say cam...

Hopefully this drive link works:
https://photos.app.goo.gl/eJM9qYHyqL1TrkUg8

Thoughts? Do you the noise is related to the vario cam system? It seems to start right @ 2500 rpm when the angle changes. (Although it seems to disappear a bit or become harder do separate from the normal engine sound as I went up the rev range). Do the actual cam angles appear normal in the sense of where they start, when they change, etc ?

05-12-2021, 12:40 PM	#1
bg305 01 Seal Gray 986 S Join Date: Sep 2019 Posts: 167	Engine noise diagnose assistance - Possible vario cam actuator/pad/chain issue? First of all thank you to everyone taking the time to read and reply, I appreciate your thoughts. Background: 2001 S, 53k miles, Fabspeed exhaust, tune (I believe done by fabspeed, it happened 2 owners ago). The tune is possibly ROW, but I do not know for sure. The reason this believed is because it does not have the normal amount of emissions monitors. I have owned it for a bit more than a year and 1/2 and replaced the AOS when i got it. So far as I know no other major work has been done (original IMS assumed, no chain guide replacements, etc). I noticed a small amount of brown plastic in the filter last oil change from the vario cam pads. It was my second oil change since owning the car and the first I did not see any plastic, but I do not know how long the oil was in it that time. Other then that the car was running like a champ. I have been monitoring my camshaft deviations since I found the plastic (this past fall) and they seem to sit around: Camshaft 1: -0.74 (this does increase to 1.60 or a bit more as it warms up and then goes back down) Camshaft 2: -9.27 Now the problem / question: I was out for a nice drive a couple of weeks ago, enjoying a corner probably in the 4-5k rpm range in 2nd, some g-forces but nothing crazy, let's call it 60% of what the car could do in that corner. I noticed mid corner the engine seem to take on a different sound. The intoxicating whale sounded more like a Subaru (Not picking on flat 4's, that is just the best way I can think to describe it). I drove it home 8-9 miles cautiously. It is possible it had lost some power, but given how gingerly/cautiously I was driving it, it is more likely just my perception. If there was a change it was not big. I finally got out today (work has been insane for a bit), put it in service mode and checked the intake for obvious leaks and the exhaust (just a quick check, nothing detailed, the car is still on the ground). So while I can't discount a leak in the intake / exhaust, I do not see any evidence to point me in that direction. My concern of course is the vario cam actuator / guides and chain. I am far from an expert on these systems but am hoping that this video I took will help show the data in a way that someone here might see something if there is an issue I had planned to try to get through the season and then replace the vario cam pads along with a pro-active ims / clutch /etc. But I think i might have to do that a bit sooner possibly. Note: at the beginning of the video I say crank angle, but meant to say cam... Hopefully this drive link works: https://photos.app.goo.gl/eJM9qYHyqL1TrkUg8 Thoughts? Do you the noise is related to the vario cam system? It seems to start right @ 2500 rpm when the angle changes. (Although it seems to disappear a bit or become harder do separate from the normal engine sound as I went up the rev range). Do the actual cam angles appear normal in the sense of where they start, when they change, etc ? Last edited by bg305; 05-12-2021 at 12:50 PM.