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Recently I replace the Variocam Ramps on my 2002 boxster S.
Reassembly went well but I have a timing problem for the cams afterwards, trying to figure out the fix.
Bank one at Idle actual cam angle is about 6, deviation is blank.
Once the car warms up to 180, the actual angle goes to close to zero, and the deviation is about 5 to 6.
Bank 2 is as you would expect, actual angle around zero at cold idle, deviation around zero at warm idle.
My recollection is that before disassembly the Durametric showed that actual angle at idle when cold was close to zero On bank one.
I read that actual angle may not represent what I think it does, I read somewhere that it represents the amount of Variocam influence on the cams, not the actual timing.
Can someone possibly explain what the actual angle means? Bonus points if someone can explain to me what exactly is wrong with my car, my best guess is either I have a bad variocam actuator problem or I assembled things with intake cam one tooth off.
By Bruce in Philly
9A1 105 308 03 VVS (02 superseded by 03 variable valve system actuator)
Anyone replace one?
What are the symptoms?
How do you identify which one may be lazy?
How many per bank? The PET digram denotes (1) so I assume that is one per side no?
These appear very easy to replace as the sit next to the spark plugs. I will be doing my plugs in a few months, early spring so I am thinking of just swapping these out.
The reason is that pesky hesitation I get under moderate load at around 2800 RPM. The dealer, as others on various boards, think it is the variocam transition. This looks like about a $150 dollar each part. I am willing to throw $300 at this issue.
I do have the Durametric Pro.... but no clue as to what to look for regarding these actuators.
Bruce in Philly
2009 C2S Coupe
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 to establish a baseline with my new Durametric tool at the time. I finally found my old hard drive with the data and to my surprise, my camshaft position 1 deviation read -8.97 cold at idle and varied down to -9.53 when driving around. Camshaft deviation, position 2 is solidly at -3.19 regardless of engine speed. On another post, I read that the durametric software may have had issues logging this parameter at the time.
No CELs, no logged errors, been running fine for the last three years, and yes, I drive the snot out of it. When I cut the oil filter I find the random tiny shards brown plastic from the variocam guides. I have a magnetic drain plug and have only seen a light amount of the typical fine metal on it. The previous owner kept meticulous records of all work done at the dealer, and no major engine work was ever done other than oil changes. I found a post about a potentially bent sensor plate on the cam where the engine is correctly timed but the sensor is reading the parameter incorrectly??
My thought at the moment is to not drive the car, pop the green plugs and check timing as well as pulling the sump pan for inspection. I also plan to log the camshaft deviations this week with the newer version of the software and see what I get. Assuming I get the same numbers, I have some questions:
1. Since the position 1 is moving around a little bit between running and idle (~0.78 degrees), should I start having my heart attack now?
2. If the timing is off by this amount, is it a simple re-timing of bank 1 if all else looks OK?
3. Dumb question also is how much timing adjustment can be made since the sprocket appears to have large slots for adjustment?
4. Another dumb question is if bank 1 skipped a tooth, would I know it already?
5. Should I just open up the bank 1 valve cover to inspect/replace the variocam pads? (trying to do the least invasive first)
6. Anything else to check/do?
Thanks for reading.
Hi, I'm new to this forum and would like to discuss a subject concerning the variocam in a '98 C2 996. I want to buy this car, the only issue is that the onboard computer shows an error/ report concerning the variocam. I had the car checked at Porsche, they told me about this. The engine is running fine and there are no other problems with the car.
Is it safe to buy this car, or should I have the seller to check/ repair the error ? The seller is providing a 3 month warrenty, but I won't use the car on a daily base.
What would you advise me to do ?