Just looking to see if someone here has ten minutes to spare at some point and hook up their durametric cable to their car and log/check a couple variables under the DME.

I'm looking to have you log:

RPM
Cam position 1 deviation
Cam position 2 deviation
Angle for camshaft, bank 1
Angle for camshaft, bank 2


Those four cam logs are grouped together on the check-box list.

I just need to know what your car is reading from a DEAD COLD start, and then what they are reading after the car warms up for ~5 minutes or so(both readings taken at idle). Another member here loaned me his Durametric to test for issues with this cam problem I'm having and I want to compare to what I have here to a car that's running good.

Here's what I have;

Engine dead cold idle (~20 seconds after startup)



Engine warmed up idle(~5 mins)



Thanks!

 

Cold start
1
-3.8
29
29
1160rpm

after approx 1 min
1
-3.8
-0.2
-0.2
910rpm

after 5 mins
-0.5
-4.5
-0.2
-0.1
845rpm

reving it up to about 2000 rpm makes the cams change to 29,drop below and they go back to 0

Hope this helps, what probs are you having?

And

 

Thanks for the info there.

This car......Two camshaft codes for "cams too retarded" after timing them using the factory tools. Been trying to diag the cause with another member and he sent me his Durametric cable to do a few tests.

Variocam is working. If I manually activate the solenoids under the softwares "drive links" tab the engine rpm dips and there is a noticeable change in the exhaust tone and smoothness of the engine idle. Returns to normal when I stop the test sequence. However the is no cycle in the Variocam system by increasing the engine rpm as you did there, almost as though the DME has put the function in a "limp mode"

the data you posted seems very close to the data I have here for the actual camshaft angle, but the camshaft deviation on this car is ~11 on either cam whereas yours is showing substantially different.

I'm wondering if that data is telling me, without any doubt, that the camshafts are mis-aligned with the crankshaft by ~11 degrees and that's what's causing my codes.

 

I wonder what is the max deviation value, that the durametric can show. On my car the deviation figures were jumping around very slightly as though they were live values.

On yours they are exactly the same on both logs almost as if thats the max value they will show, and the true values are greater, can you remember if they were jumping around ? Also on my car as it warmed up they changed by half a degree or so,did you notice this?

Also, as you said, the fact that yours didn't advance when revved may mean something, but what?

And

 

The deviation numbers did not change at all when warmed up for the first data log but I also didn't let it run for more than a few minutes. I just logged it again and they were slightly lower(~10.98/11.02) and did move around a tiny bit after warming up for a bit, but nothing quite like yours.

The cam angle numbers do jump around a couple tenths of a degree while running. I just did the second log and revved the motor up to ~3.5-4K and there was no big change change in the angle showing on the durametric, thus assuming the variocam was not being activated. Did a quick check on the drive links, and the solenoids activated when I clicked the button/tab.

I too do not know what the "camshaft deviation" listed by the durametric actually means. I'm assuming it's a range of how far off the cam and crank are out of sync, shown in degrees. I also do not know what the acceptable range/limit is for the DME, and what the max deviation is before it trips a CEL in the dash.

It just looks to me that I'm going to have to just bite the bullet and yank the motor out again and retime the camshafts. I already ordered the new camshaft bolts, just incase I had to do it. should be here in a couple days I think.

do appreciate the help

Anyone else that wants to add to this, or datalog their car and post their results please do. The more the better.

 

I think I would be trying to get some more data before taking the motor out!!
There must be a few people here who regularly have a logger connected to different cars who could tell you if 11 is a normal value or not?

I'm also wondering how you could have got the timing wrong the first time round. I haven't done it but it sounds fairly straight forward.I would have thought you would have got it dead right or dead wrong but seeing as it is running it can't be massively out.

The only thing I can think of, is that you turned the actuator to the wrong stop?
Or that the timing is correct and there is another issue thats stopping the cams advancing when revved,and the DME is setting the codes because its expecting but not seeing them advance. This seems like a long shot but these DME work in strange ways sometimes.

And

 

Yessir the actuators were rotated to full left stop as the manual indicates. In comparison to the older aircooled motors, the timing on these motors is so simple and I rebuild and time alot of those old p-car motors.

I know that when I clear the codes out via the Durametric, they instantly pop back up apon starting which means the DME is registering the fault immediately. I suppose I'll hold off for the night and let other people respond to see what they might have to say and or data to contribute.

 

at idle 0 deg, at load 30 deg is okay....both side should do the same...

a large deviation shows either timing chains lengthened or cam shaft sensor not in order.....11 deg deviation is lot ..normal between 0-6 deg

but both cams with 11 deg......? something is wrong.....woodroof key?/ timing adjusting?

 

A few random thoughts

Is the crankshaft position sensor adjustable, could it be in the wrong position?

Have you made any other changes at the same time eg different flywheel that may have its timing cog in the wrong position?

Could there be a fault with the cam position sensors?

It seems unlikely you timed it wrong, but were the chains definitely under tension as you locked the cam sprocket bolts?

Is it possible to fit the cams to the wrong sides?

Is it possible to fit the timing brackets to the wrong side?

Is the woodruff key definitely there on the crank cog as mentioned above, and is it worn allowing play?

That all I can think of for now

And

 

good question...thats definatly the route

 

bam, there's the data I was hoping to get. Thank you. If that's the range it normally operates in, the 11 degrees would certainly trip a fault code. Damn!




All good valid questions. Point by point:

-CPS adjustable in spacing away from the trigger wheel on the flywheel, but virtually none to change it's relation in angle to the crank.

-Everything except the rods/pistons/crank is the same. Original timing gear fitted per OEM spec with new woodruff key on the crank gear.

-I would think that if there was a fault in the cam angle sensors I would have fault codes for them as well.

-Chains are new OEM parts(IWIs) and were tensioned

-All the parts for banks 1 and 2 were marked and removed and placed into corresponding marked containers. I don't think it's even possible to swap the intake cams and still have them line up with the timing plates. they are different parts numbers in the PET.

-The timing slides/guide rails are all different part numbers and side specific. Wont swap around. These were also marked and placed into marked bins for the left/right cylinder banks. Even when cleaning the part I only did one side at a time until all parts were cleaned, dried, and wrapped/put back in the crates. I'm pretty **** about that process to avoid mixing parts up, and to keep parts from one engine from getting mixed up with those from another.

-Key was brand new.

 

OK so lets assume the electronics are saying the cams are out by 11 degrees, and that's enough to trip the CEL and to also stop them advancing at higher engine speeds.

How could this happen? well either you simply timed it wrong and it just needs resetting, or you timed it right and the signals from the cams and crank are wrong for another reason

Is the replacement crank a standard 996t part? I ask because its the only part you've replaced that could cause a problem if it had a difference to the original

If its after market could it be machined wrong so the cams are timed correctly with respect to TDC but the flywheel is out by 11 degrees or the crank pulley is out if using timing marks on the pulley to set TDC ?

Could the crank be from a different version of the engine and have a slight difference eg a 993 causing the same effect


I don't know how the manual says to set the crank position, do you actually set it to TDC using a dial gauge through a plug hole if so did you recheck it at the end using the dial gauge to confirm it hadn't moved.

or if you align a timing mark on the crank pulley for example to set the position could you have aligned it to the wrong mark?

Maybe you will take it apart and find the timing plates don't line up and you've somehow made a mistake, and simply resetting them will fix the problem and you'll think Doh I wonder how I did that!!

I know I've done silly things in the past,and can't work out what I was thinking at the time.

hopefully you will get it sorted soon, and will laugh about it in the future

And

 

Thanks And. At this point I am laughing about it, but it's that 'son of a #$%^@#$%^" type sarcastic laugh at myself. The crank was a std/std OEM 996T part from an m96.70 It was purchased from Kevin @ Ultimate Motor Werks and was perfect all around. the only thing I had to do to the crankshaft was install the IMS timing gear to the crank with the special collar and sized snap rings. New woodruff key was installed. It's a process i'm very familiar with and have done to countless Porsche crankshafts rebuilding engines over the past ~15+ years.


I've already started pulling the motor out and it should be down and on the ground within the hour. Everything to me is working electronically, and the data that's coming from the durametric in my mind is telling me the cams are off(for whatever reason). If nothing else at least I'll have sound mind knowing that after going back into this motor and checking the cam timing out, that I will know with 100% certainty that it'll be correct this go around, as i'm going to be paying very close attention to everything and triple checking all the measurements and tools.

I do appreciate the help though. Nice being able to compare data to a known working car as it answers quite a few questions right off the bat.

I see you're in england. If you're ever over in switzerland, look up Dubler Chocolate(Mohrenkompf). My sister(Amanda Hennessy) works over there and helps run the place and the owner, Robert Dubler, is a really good friend of mine and just wonderful. Tell them you Helped me out(Adam Hennessy) and i'm positive they'll compensate you with some good chocolate ..... Their website http://www.dubler.net/

-Adam

 

Welp, motor's out. Only time will tell now

 

Well found the issue out, rather stupid one. Crank was off ~8 degrees retarded. Don't know why I did it, I've built these motors many times over before. Just had a brain lapse or something i guess. Dial indicators and degree wheels don't lie though.

Anyway, going to get the motor ready to time the cams again. I've got to remove all the timing gears and degrease/clean the friction faces of the gears and cams, and get all the VC surfaces clean again for new sealant.

Thanks for all the help though. That info is what directed me to pull the engine without goofing around the problem any longer