cam timing on 3 chain boxster

[systemthree]

I was doing a IMS replacement on my 2004 boxster S. I put the engine to TDC installed locking tool put the camlock tool in cams behind passenger seat replaced the IMS bearing removed the looking tool rotated the engine to check timing it is now about 10-15 degrees off. I removed the scavenge pump loosened the four bolts on the timing adjustment rotated the engine back to TDC with cam tool in place. I then put the locking pin in place and tightened the four bolts. Rotated the engine again and found it to be off 10-15 the same as it was. Can someone please tell me what is going on?

[JFP in PA]

Originally Posted by systemthree

I was doing a IMS replacement on my 2004 boxster S. I put the engine to TDC installed locking tool put the camlock tool in cams behind passenger seat replaced the IMS bearing removed the looking tool rotated the engine to check timing it is now about 10-15 degrees off. I removed the scavenge pump loosened the four bolts on the timing adjustment rotated the engine back to TDC with cam tool in place. I then put the locking pin in place and tightened the four bolts. Rotated the engine again and found it to be off 10-15 the same as it was. Can someone please tell me what is going on?

Sure, you were supposed to lock the cam from the flywheel end of the engine, not from behind the passengers seat (per the LN Engineering instructions).

[systemthree]

Originally Posted by systemthree

I was doing a IMS replacement on my 2004 boxster S. I put the engine to TDC installed locking tool put the camlock tool in cams behind passenger seat replaced the IMS bearing removed the looking tool rotated the engine to check timing it is now about 10-15 degrees off. I removed the scavenge pump loosened the four bolts on the timing adjustment rotated the engine back to TDC with cam tool in place. I then put the locking pin in place and tightened the four bolts. Rotated the engine again and found it to be off 10-15 the same as it was. Can someone please tell me what is going on?

I checked the cam timing on the driver side and found the same thing, 10-15 degrees off. How do I get it back in time?

[JFP in PA]

Originally Posted by systemthree

I checked the cam timing on the driver side and found the same thing, 10-15 degrees off. How do I get it back in time?

You need to perform what Porsche calls "cam allocation" or timing. It has probably been written up on one of the websites (Pelican, 986 Forum, RennTech, etc.).

[afterburn 549]

Originally Posted by JFP in PA

You need to perform what Porsche calls "cam allocation" or timing. It has probably been written up on one of the websites (Pelican, 986 Forum, RennTech, etc.).

I would say that was not very help full..

[JFP in PA]

Originally Posted by afterburn 549

I would say that was not very help full..

That's nice. The cam allocation procedure runs about 14 pages, two sided, in the OEM service manual set; which would be more than just a little difficult to correctly sum up in 25 words or less. This subject has been covered as DIY's on multiple websites, and "search" is your most helpful friend in these cases....................

[afterburn 549]

OK, sorry
Its just i have been in those dire need circumstances and someone pipes up "do a search" ...
Its kind of the last thing you want to read.......searches on this board is pretty dam hard..
BUT
I did not know it was 14 pages!
H>S> ! LOL

[systemthree]

Originally Posted by systemthree

I was doing a IMS replacement on my 2004 boxster S. I put the engine to TDC installed locking tool put the cam-lock tool in cams behind passenger seat replaced the IMS bearing removed the looking tool rotated the engine to check timing it is now about 10-15 degrees off. I removed the scavenge pump loosened the four bolts on the timing adjustment rotated the engine back to TDC with cam tool in place. I then put the locking pin in place and tightened the four bolts. Rotated the engine again and found it to be off 10-15 the same as it was. Can someone please tell me what is going on?

I got the engine back in time, at least I thought I had it. Cranked the engine everything look good for the first 10 min. no engine codes. I restarted the engine again let it run for about 5 min. and the check engine light came on and I found I had "advanced cam timing codes" P0011 and P0021 I checked the timing at TDC and the cam lock tool lines up. Before I moved the cam timing the cam tool lined up at 10-15 degrees past TDC. Any thoughts?

[afterburn 549]

My lazy thought, dose it run ok?
live with it.

[systemthree]

Originally Posted by systemthree

I was doing a IMS replacement on my 2004 boxster S. I put the engine to TDC installed locking tool put the camlock tool in cams behind passenger seat replaced the IMS bearing removed the looking tool rotated the engine to check timing it is now about 10-15 degrees off. I removed the scavenge pump loosened the four bolts on the timing adjustment rotated the engine back to TDC with cam tool in place. I then put the locking pin in place and tightened the four bolts. Rotated the engine again and found it to be off 10-15 the same as it was. Can someone please tell me what is going on?

Engine ran fine, no problem only P0011 and P0021 codes and "check engine" light on.

[afterburn 549]

My answer is /was a hip shot idea...until you pull it for an other reason...maybe by then you will have a clear answer how to fix this and not how to share with us

[PorscheVTEC]

Here's how to fix this in car.

Assuming its Bank 1 that is out of time. Bank 2 can be done in a similar manner I would imagine.

The idea is that we are going to lock the camshafts. Then loosen the camshaft sprockets. Then rotate the crank into TDC and re-secure the sprokets. The cam sprockets are not keyed. They are held in place by friction.

You need the timing tool that holds both camshafts
2 new green cam caps (996 104 215 54, Cam Plug)
1 new Brown Cam Plug (996 104 216 02, Cam Plug)
Porsche says to replace the intake cam bolt when removing it. I didn't. Up to you.


1. Remove the firewall access panel behind the seats.

2. Remove the Green Cam Plugs on the Passenger side Cyl Head

3. Rotate engine clock wise using 24mm Wrench until the mark on the crank pulley lines up with the mark on the crankcase.

3. Note what direction the cams need to rotate to make the locking slots vertical. This comes into effect later when setting up the exhaust cam.

3. Now rotate the crank so that the cam slots are vertical and the holding tool can be installed. (this guide assumes the chain skipped on the IMS gear, if only one cam skipped this guide could point you in a direction.)

4. Install the cam holding tool. Bolt it down. If it doesn't fit try rotating the crank 360deg. If its close to fitting move the crank back or forward a little to get it to line up.
Note: You can rotate this engine by hand forward or backwards as needed. Obviously for major movements move clockwise but for correcting small stuff you can move it backwards without any issues.

5. Remove the Exhaust again. (Leave manifolds on, for the love of god.)

6. Remove the Black crescent bracket with the wires on it from the bell-housing area. Its the big one. You know which one. 4 15mm bolts and the 13mm through bolt attached to the crank case.

7. Drain the oil into a clean oil catch pan. We will reuse the oil.

8. Remove the timing chain tensioner with a 32mm Socket. The one on the cylinder head we are working on. Leave the other ones where they belong.

9. Remove the oil scavenge pump. 4 x 10mm bolts on the corners. If you take off the inner bolts your going to have to put it back together. Use a flat head to gently pry the scavenge pump out of the head. Some say mark which was is up. Solid Advice.

10. Remove the 4 x 10mm bolts holding the cam adjuster sprocket to the camshaft. Be super careful not to drop the bolts down into the engine. If you do you will need to get new bolts. Other work may be required as well.

11. The idea with the exhaust cam is to get the slots set up so that when you rotate the crank later the bolts wont interfere with the edge of the slots. I removed the cam sprocket and reinstalled it a few times. I ended up putting the bolt hols in the center of each slot because I was only out by a tooth. Should be similar for anyone reading this.

12. With the bolt holes in the middle of the slots reinstall all 4 bolts but not even finger tight. Just touching the cam sprocket. We want it to be free to move but not free to fall off.

13. Get your 16mm socket and a breaker bar.

14. On the intake cam you will see the cam bolt and a larger hex shape behind it. The part is a spacer and is not connected to anything.

15. The Intake cam bolt has normal threads so Lefty Loosey still applies here.

16. Loosen the bolt with the breaker bar. Its gonna be tight.

17. Once its loose do the same as the exhaust. The bolt is holding the sprocket in place but the sprocket is free to move.

18. Reinstall the chain tensioner.

19. Go in the car and rotate the crank to the TDC mark. Use a 7mm or similar metal dowel to lock the crank pulley in TDC.

20. At this point we know the crank is in TDC. We know the Cams are in the correct position.

21. Remove one bolt from the exhaust sprocket and make sure the bolt hole is not "against" the end of the slot on the sprocket. I just want to make sure nothing got binded up. Mine were fine with a few mm to spare.

22. Tighten the 4 bolts to 30Nm.

23. Tighten the intake cam sprocket bolt to 50Nm then an additional 110deg. (look up torque angle measuring, I have a fancy torque wrench that measures angle. I found I had room for about 33deg of rotation in that area. You can definitely make a good guess at getting there. My final torque was around 100Nm, yours may be different because torque angle tightening is about stretching the bolt and not so much the torque applied, but I share the info for reference.)

24. Now put everything back together and your good to go.

I replied to this thread because I kept searching for this info and I could only find the questions. Never the answer.

I probably wont be back here. Good luck if I messed up the directions.

[PorscheVTEC]

Originally Posted by JFP in PA

That's nice. The cam allocation procedure runs about 14 pages, two sided, in the OEM service manual set; which would be more than just a little difficult to correctly sum up in 25 words or less. This subject has been covered as DIY's on multiple websites, and "search" is your most helpful friend in these cases....................

No its not. See the post above. And stop being a dick to everyone FFS. Nothing you wrote in this post has helped anyone. All the information you were able to tell us turned out to be bull****. The procedure is 14 pages single sided.

[JFP in PA]

Originally Posted by PorscheVTEC

I probably wont be back here.

Good, you won't be missed...…………...

[targaguy]

Thanks Porsche VTEC. Your instructions helped me get the cam timing reset on my 3-chain. It was not hard and I had to do it twice, because the exhaust sprocket bolts weren't centered. A note to anyone that has replaced the chain guides. Before the final torque of the intake sprocket bolt, be sure to tighten down the tensioner, the small center chain guide and all of the cam bearing caps. The high torque will rotate the intake cam and sprocket unless it is all locked down. I did not have the correct cam counter tool, so the second time I used an adjustable wrench to hold the clamp nut while torquing and adding the 110 degree angle to the center nut. Worked like a charm.

And, although you may not be back on this forum, I wanted to correct the record on the torque setting for the four exhaust cam sprocket bolts.

Quote:

22. Tighten the 4 bolts to 30Nm.

The Porsche repair manual states the correct torque is 14Nm. At 30Nm someone will probably snap a bolt. I got mine to 20Nm before they felt too tight. Glad I stopped there to check the manual. I backed them off to 13Nm and then finished them off at 14Nm on my digital torque wrench. That tool is an absolute must!