986 2.7 Camshaft Deviation

[mikefocke]

Recall that there are at least 28 failure causes in this engine. Do em one at a time and spend your life or your savings. Try to do them all and do both.

[jluetjen]

Disclaimer -- I've got the adjuster ramps, seals, cam adjustment tools, etc. on order. I'm also going to inspect the oil filter and get another oil test done.

Original problem statement: Check engine light (camshaft deviation) just as the car is due for its annual inspection.

My initial reaction?



... And then then I ( like many Porsche owners) was going spend the $,$$$ or potentially $$,$$$ to have the engine dropped and everything replaced, or worse sell the car for $ with the "check engine" light glowing.

Upon further reflection, I wonder if I was being too binary about the experience.

Sure. Ramps can fail and clog up oil passages. But let's give Porsche a little bit of credit. Not every car is a worst case. I also don't know if the ramps had previously been done on the car. For example, the IMS bearing had been replaced, but there was no clue of this nor a clutch replacement in the Carfax history.

Assuming that I don't see chunks of plastic in filter -- I think I may just re-align the cams, check everything again with the Durometric while I put the required 60 miles on the car and submit it for it's inspection. If the fault was due to "normal" wear, and there is adjustment left, and the check-engine light doesn't come back on, it should be fine for the immediate future.

All of this being said, since I've already paid for the tools and parts, I'm still going to take the cams out and replace the ramps, etc. But I may do it next spring when the weather is warmer and I have my 911 to drive around in.

As usual, I'll continue to post my findings and results on this subject on this thread.

[Homeoboxter]

Originally Posted by jluetjen

If the fault was due to "normal" wear, and there is adjustment left, and the check-engine light doesn't come back on, it should be fine for the immediate future.

I'm afraid there's not much room for adjustment in this case. If you realign everything, that is going to affect primarily your exhaust camshaft and that's independent on the variocam. The variocam units adjust the intake camshafts only and there is no adjustment there. So, unless your long chains are badly stretched out or your chain has skipped a tooth already, you will find that the alignment is fine. But that does not mean the post variocam alignment is good, and that can't be adjusted.

Check pictures here for reference:
https://986forum.com/forums/show-tell-gallery/86442-meridian-boxster-rebuild-project-24-a.html

It's worth checking though, inspect the timing and let us know what you find.

Another thing you can try there is to inspect the chain pads with a borescope through the cam alignment holes. There's very little room to do this and you have to play a lot until you find the right angle, but that can give you a hint about the condition of the pads.

Good luck!

[jluetjen]

Originally Posted by Homeoboxter

Another thing you can try there is to inspect the chain pads with a borescope through the cam alignment holes. There's very little room to do this and you have to play a lot until you find the right angle, but that can give you a hint about the condition of the pads.

I was thinking the same thing since I have a borescope.

[jluetjen]

Originally Posted by Homeoboxter

I'm afraid there's not much room for adjustment in this case. If you realign everything, that is going to affect primarily your exhaust camshaft and that's independent on the variocam. The variocam units adjust the intake camshafts only and there is no adjustment there. So, unless your long chains are badly stretched out or your chain has skipped a tooth already, you will find that the alignment is fine. But that does not mean the post variocam alignment is good, and that can't be adjusted.

Good points. Not much of a benefit.

I just got the tools in last night. I'm ready to get started.