Camshaft deviation-1999 C2

[dcdrechsel]

Using the Durametric Software -Bank1 deviation is flatlined at 12 degrees .There is no change from idle thru 6000 rpm.

The Durametric folks have had reports of a broken actuator spring causing this -stuck in advanced postioin .

In my case using the bank 1 drive link the idle changes dramatically-which seems to indicate the actuator isn't stuck.

I would like to try same test on bank 2 but DME/durametric doesn't report that side .

Cel is not tripping-no codes .

I guess there are two questions -has anyone else experienced this ?If the timing is off -is the DME smart enough to not advance beyond 12 degrees ?

It would be nice to get a handle on this before taking it apart .

Any insight or suggestions would be most appreciated .

Dave

[insite]

any drivability issues? why did you bother checking the deviation? it's possible your timing is off. this happens when chains stretch, tensioners wear, or in some cases, they're set poorly from the factory. how many miles on the car? have you physically verified the timing?

Using the Durametric Software -Bank1 deviation is flatlined at 12 degrees .There is no change from idle thru 6000 rpm.

The Durametric folks have had reports of a broken actuator spring causing this -stuck in advanced postioin .

In my case using the bank 1 drive link the idle changes dramatically-which seems to indicate the actuator isn't stuck.

I would like to try same test on bank 2 but DME/durametric doesn't report that side .

Cel is not tripping-no codes .

I guess there are two questions -has anyone else experienced this ?If the timing is off -is the DME smart enough to not advance beyond 12 degrees ?

It would be nice to get a handle on this before taking it apart .

Any insight or suggestions would be most appreciated .

Dave

[dcdrechsel]

No driveability issues.Why did I check it ?About to do IMS bearing and wanted a baseline .Have I checked the timing ? Not yet .116,000 miles -I am sure chains are stretched .Obvioiusly something isn't right -the cam deviation is flatlined at 12 degrees yet when I exercise the drive link the motor changes significantly- lumpy idle.

It could be as simple as timing is off and at max therefore dme won't advance cams .The question is the dme programmed to do that?The reason It would be nice to get a handle on this is that if I have to pull the actuator I will drop the motor -if not just the trans for the IMS bearing .

Dave

[RFM]

It is not possible to activate bank 2 camshaft deviation on older cars with a diagnostic tool, you should do the test manually. Let the engine idle, remove the actuator connector and put 12V+ and ground from a spare battery on the 2 pins connector (actuator wire), you should have the same lumpy idle as on bank 1 now, which means both actuators are fine, if not, check the actuator bank 2. I would replace both adjuster chains and plastic chain guides actually after 116.000 miles. Now fix the crankshaft and the camshafts bank 1, to check the timing bank 1 with the special tools, rotate the crankshaft 360° and do the same on bank 2, adjust if necessary.

[dcdrechsel]

RFM -thank you for the response .Bank 2 produces same lumpy idle -have no clue what devation is since dme doesn't report it .I think you are right on replacing chains and guides as well .Still would like to understand why deviation is flatlined .or not moving .

Dave

[Cloudsurfer]

Well, unfortunately, to replace the chains you need to split the cases, which means tearing the entire engine down, so that's not going to be an option.

Keep in mind that the deviation value is actually a computed value. What's better is to compare the actual camshaft values that the DME commands vs the camshaft values as reported from the hall sensor. You should be able to read this for both banks.

[RFM]

dcdrechsel talked about the camshaft deviation chains IMHO, since it fulfils the proper functioning of this system in doubt, according to his previous posts.

[dcdrechsel]

Cloudsurfer-DME values would be great .I don't think you can do that with the Durametric .By chance do you know how to test the hall sensor?Here is why:with ignition on ,engine off Durametric reports 12 degree deviation .I would think it would be 0 .

As far as chains -I believe Jake has chains with a master link available .Connect old to new and weave thru engine .

Thanks

Dave

[Dharn55]

The wold be great is there were replacement chains that could be installed without a total tear down of the engine. Are they really available? And for what engines? 3.4 with old style chains, 3.4 with new style chains, 3.6 ? This would only be possible for the IMS to crank chains, with the cam covers off, no way to get to the IMS to Crank chain. And on the 3.4 the cam to cam chains are pretty easy to replace. Have not see or heard of these replacement chains with a master link. You would have to cut the old chains and somehow splice in the new chains.

[1schoir]

....

Have not see or heard of these replacement chains with a master link. You would have to cut the old chains and somehow splice in the new chains.

Dharn:

These type of chains have been available for decades, although I was not aware they were available for specific Porsche engines.

I replaced two timing chains on my '71 BMW 2002 with this type of chain with the master link. You just cut one of the links on the old chain and attach it to one end of the new chain. Then, you just pull the non-attached side of the old chain until you can work around the new chain to make the attached end of the new chain reappear. Then you detach and discard the old chain and complete the circle of the new chain by fastening the master link onto the two ends of the new chain.

Regards, Maurice.

[dcdrechsel]

Do a search on rennlist- timing chain replacement by big Ev -one of the responses is from Jake indicating he is having them made .It's his second post .His first post is about splitting cases -keep going ..Another source is Parts Geek .I am sure there are a few more .

Dave

[txhokie4life]

I've run this test on my '01 S with a duramatic

I do it on a bank and I get a spike in RPM, then back to idle with maybe a slight change.

On the other bank it get essentially no effect, with the slight idle change.

which is correct?

I get a ticking sound coming from my drivers side. Wondering if it is my camshaft vario-cam actuator?

thanks,

Mike

[dcdrechsel]

Mike -I think the actual value readings would be more informative and can be compared to the set values .For example -the 1999 set value at idle is 0 + or - 6 degrees .That changes as you increase engine rpm .I don't remember to what .The drive link is more of a continuity test .The durametric software is supposed to be able do a concurrent operation -drive link and actual value reading -which in my case would have been helpful. But there is a bug and will be fixed in a future release .

Dave

[txhokie4life]

Mike -I think the actual value readings would be more informative and can be compared to the set values .For example -the 1999 set value at idle is 0 + or - 6 degrees .That changes as you increase engine rpm .I don't remember to what .The drive link is more of a continuity test .The durametric software is supposed to be able do a concurrent operation -drive link and actual value reading -which in my case would have been helpful. But there is a bug and will be fixed in a future release .

Dave

I'm thinking one of my tensioner hydraulic actuators maybe bad -- that was why I was trying to understand what exactly to expect when the drive link might expect to do.

Next time I get a chance I'll see if I can monitor the camshaft with the Duramatic, get her up in the rpm range -- and I should see them track -- if they don't then I know something is up.

I get a nice ticking sound from the drivers side -- hoping that this might be it -- not that its an easy fix -- but I like to get things resolved.

thanks,

mike