Ottomotion

Hello....I am new to posting in this forum. I have posted on the 986 forum and look forward to being part of this knowledgeable community as well...

While waiting on my SAI system to get to pass mode, I am tackling another issue.

Durametric is showing a p1325 and p1341. The CEL has never come on.

My camshaft Deviations have always been steady:
@
Cam 1 -0.75
Cam 2 1.28
...since I reinstalled the motor.
Engine seems to be running great and all of these values are from the car being well warmed up.

Looking at the 'Actual Angle for Inlet Cam Bank 1 and 2' at idle I am seeing anywhere from .4 to -.55 avg for the high and low ends of the reading...both cams.

Looking at the 'Spec. Angle for Inlet Cam Bank 1 and 2' I see a reading of @ .4 or lower for bank 2

...but at idle, bank 1 is a flat-line 0.00.

If I blip the throttle, it (cam 1) can soar to over 30!......but quickly settles in to @ whatever bank 1 cam is reading.

Any thoughts as to what might be going on?

__________________
Otto

2003 Boxster S
1939 Ford DeLuxe Coupe w/392 Hemi
1984 Suby Vanagon Westfalia

Macster

P1325 Camshaft Adjustment, Bank 2 – Signal Implausible.

Possible fault causes:
– Dirt in system
– Solenoid hydraulic valve mechanically blocked.

Ottomotion

Thanks for your excellent reply. I am leaning towards a bad solenoid actuator. I think maybe a quick diagnostic would be to swap the bank 1 w/the bank 2 actuator and see if there is a change in the readings.
I have cleared codes once after the engine install and they did come back. I will clear again and report back.

I still dont know what the difference is between Actual and Spec. cam angles. What are Spec cam angles?

Thanks

Macster

Swapping actuators is a bit of work to get to them. And I am not sure if they are interchangeable from bank to bank. Getting to the solenoids is bad enough. These however might be interchangeable.

Actual angle is I'd offer as a WAG what is being measured/reported. Spec is what this should be or what range it should be.

Ottomotion

UPDATE:
I figured since I have 100K on the car and the solenoids are probably original, I will replace them. The 03-04 are accessible outside the cam-covers and not too bad to pull.

I ordered two new ones. When they arrived I bench tested them and there was a noticeable difference between the sound and action of the old and new.
I installed the new ones and hooked up the Durametric and went for a road test. I cleared all codes prior to the test.

During the test, something strange happened. The Durametric Spec. Angle for Inlet Cam Bank 1 is now looking fine...less than 1* throughout the RPM range....but now Bank 2 is flat-line at idle and then swings wildly up to sometimes 40*!!...but unlike the way Bank 1 was acting prior, it does not return to a comfortable range, Instead it stays @ 5-6*....until put under load, then it swing way out again....or if left to fall back to idle, flat-lines.

No more p1341 but p1325 did show up again. Still no CEL and car seems to run great.

Thoughts?

Macster

I gave away my Boxster OBD2 references so the following is what I found with a search.

P1325 Camshaft Adjustment, Bank 2 – Signal Implausible

Possible fault cause:
- Dirt in system
- Solenoid hydraulic valve mechanically blocked


I can suggest some things to check for.

First double check all solenoid electrical connections.

Double check all camshaft position sensor connections.

Any small greenish bits of rubber in the oil filter housing oil? If so these can be from a chain tensioner o-ring. The implication is the tensioner that controls the actuator chain guide/rails that move the intake cam chain to cause the intake cam timing to change have failed. Now it might be the tensioner o-ring failed a while back -- and you have been dealing with more than one issue -- and if the oil was changed the bits were lost/thrown out with the previous old oil.

When my Boxster experienced some engine weirdness the pending code pointed to the VarioCam system. The tech said with the Boxster there is no way to distinguish between a bad solenoid or actuator from outside. While I don't recall the tech saying this it might be possible once the solenoid is out of the engine one may be able to bench test it and if so and if it fails the test to know it needs to be replaced but there is no way to test the actuator other than installing the new solenoid and buttoning up the engine and then road testing the car. If the symptoms return then it is back into the engine to replace the actuator.

What he said was SOP for these kinds of problems was to replace both the solenoid and actuator. Sorry, but the story gets a little longer... For reasons unknown to me the tech elected to just replace the solenoid. The symptoms returned very soon after I got the car back and I took the car back and the dealer ate the cost of duplication of labor to replace the actuator. Had the tech asked me I would have of course agreed to replace both the solenoid and the actuator and the dealer management knew me well enough to know this. I had to pay for the actuator and the extra labor required once the solenoid is out of the way. Afterwards the symptoms were gone and stayed gone.

I just wanted to highlight that while one can possible identify a bad solenoid and replace it that may only address half the problem. The other half may be with the actuator.

I had the old actuator and the new one to look at and except for a bit deeper groove worn in the chain rails of the old one both looked the same. There is really nothing to see. All the magical stuff is inside.

I do not know of any way to test the actuator on the bench. It works via oil pressure that is controlled by the solenoid.

If there is "dirt" in the system I do not know of any way to remove this. In the case of lifters that are noisy and one of the causes can be "dirt" in the system the Porsche solution is to replace all the lifters on the noisy bank. Thus I expect the solution for suspected "dirt" in the actuator is to replace the actuator.

My point in all of the above is to suggest that the problem if not due to a wiring connection -- which I believe unlikely but you must not skimp on your sanity check of the wiring connections for I could be wrong -- the problem is probably due to a bad actuator.

Ottomotion

I *think* that since mine is an 03-04 motor, I don't have an actuator like the 5 chain motors do. I think my solenoids do something to control oil flow which somehow acts on the big vanes which are located on the intake cam sprockets.
You can get a feel for my level of expertise by my use of words such as 'I think', 'something' and 'some how'...so don't hesitate to correct me....
I think it would be good to go in and recheck all of the connections to the solenoids, I will pull the solenoids again, make sure they are functioning properly on the bench again. There are also screens at the nose end of the solenoid I will pull and clean.
If that doesn't do the trick, then I would think the vane has somehow failed or there is a blockage to the oil passage that feeds them/it. If that is the case, then that is really bad and would mean probably re-dropping the motor and tearing into it again.

With all that being said, I still am stuck on why the symptom changed banks.....that has me thinking electrical and therefore ECU/DME problem.

But I don't know what to or how to look for that.

As always, thanks for your time and efforts in helping. It is greatly appreciated.

Macster

Your level of expertise is apparently better than mine. You are right the actuator I'm thinking of is not present in the 2003+ models. This doesn't mean that what the solenoid causes to activate isn't working right.

While there are exceptions generally the ECU is most often blameless in these cases.

And there is that old last thing touched first thing suspected to keep in mind, so a sanity check of one's work is called for. This is often hard to do because one feels like he is covering old ground. But it is critical to be thorough and accurate, to do a good job.

For why the symptom apparently changed sides if you tell me you had both sides disconnected then reconnected them, I'm going with a connector issue. Maybe just an partially seated connector. Your check of the various connections will I'm sure if this is the case find this.

Ottomotion

Found some time this weekend to pull the solenoid for bank #2...the side that was showing Spec. Cam values out of wack as described above in post #5. I also pulled the screen in the solenoid hole and did a thorough cleaning of of both screen and solenoid. I bench tested the solenoid to make sure it was making all the right sounds and it was. In addition, I cleaned the electrical contacts for the solenoid and plug.
I reassembled everything and started the car and let it idle for about 5 minutes while I buttoned up the garage and readied the Durametric for the road test.
I brought up the Actual Cam values and Spec Cam values for both banks on the Durametric. The Spec Cam for bank #2 was better....no flat-line/0.00* at idle, instead it was dancing along nicely at +/-1* like the others, but when accelerating, it would swing wildly out to @ 40*. I got to the end of the neighborhood development and thought I better check to see if there were any codes. P1325 was, of course, present. (still no CEL).
I decided to clear the code and proceed with my test drive to see if there was any improvement as the car warmed up and was driven.
within about 2 miles, something bizarre happened. Bank #1 started to act in the same way as bank #2. For about 2 miles of driving, some stop and go, the banks were very close to each other in their Spec Cam values. Both would swing wildly up to @ 40* when accelerating and then settle to @ 5-6* when just normal driving. I kept waiting to hear the whole motor grenade behind me, but I pressed on.
Within another mile or two, bank #2 stopped the symptoms it had been exhibiting as described in the previous postings. It was dancing along @ +/- 1*
Bank #1 had apparently taken over the crazy behavior. I pulled over and checked for codes. P1325 was gone....only to be replaced by......you probably already guessed it....P1341.
Stunned, I thought I better keep test driving to see if anything would change again. Freeway drive now for @ 10 miles. Bank #1 swinging wildly out to 40* under acceleration and settling back to 5-6* while driving.
Then, almost back to the garage, the Spec Cam reading for Bank # 1 went flat line/0.00*. It didn't matter if I accelerated, idled, drove....it was flat-line while the others Actual Cam and Spec Cam readings for both banks were +/- 1*. I pulled over and checked for codes. The p1341 was still showing (since I had never cleared it?) so I cleared it.
I turned around and went back out for @ 10 more miles of driving. The flat-line for Bank 1 Spec Cam still present and the others still normal.
I finally got back to the garage, checked for codes....and no codes were showing.

I have an appointment with a psychotherapist Monday afternoon.

Otto

Ottomotion

Could the bank #2 head having been machined when I pulled it to replace the bent valve/broken spring be causing havoc with the system? Total amount shaved would be @ .003.

I did not pull Bank #1 head...just replaced all springs and lifters.

I wouldn't think so but I believe Porsche's are designed with pretty tight tolerances....

Just spit-balling here.

Maybe someone with deeper knowledge about engine builds can chime in?

Ottomotion

Spent some time tinkering with the Durametric today.
When the p1325 or p1341 code is cleared and then Actual Values for Actual Camshaft and Spec. Camshaft Angles are selected on the Durametric, the result is a flat-line for both bank 1 & 2 for a mile or so. Then, they will both swing wildly out, up to but never exceeding 40* for both banks at the same time. Again, this usually lasts for a mile or so.
Then, one of the banks will return to the ideal +/- 1*, right in line with the Actual Camshaft Angles for both banks.
The other bank's Spec. Angle will continue to be out of wack, swinging wildly upwards of 40*.

Stop, check codes and whichever bank had the Spec Camshaft Angle out of wack would throw a p1341 or p1325 depending on the side. The p1341 showed up 3 times, and the p1325 showed up 2.

Actual Camshaft Angles are always great.

Never a CEL. Car runs great.

I know I am not getting much feedback....I am still hoping someone who has had a similar experience might stumble in to this thread and offer some form of direction....

Otto

bekks

Not much help to you now, but once I have mine going in about a month I will monitor the camshaft angles to see what readings I get.

AnthonyGS

Ottomotion

Thanks for the reply. Good suggestion on the porsche tool. I am just about to hand it off to the dealer....but not yet.
Base timing is fine. Never more than 1* off for the 'Actual Cam Angles". I would assume that the motor running great and no CEL would support that as well.
The 'Spec Cam Angle' swinging out to 40* is the problem that's throwing the codes.

**I still don't know what the difference is between 'Actual' and 'Spec' cam angles.**

If the cams were 40* out, I would think I would have piston meets valve FUBAR happening.
The 40* reading and related codes switching from one bank to the other is the root. Why would the system show that and what would cause that....?

The cams were locked with proper tools when repair was done. Cams were marked 6 ways from sunday and everything went back in the way it was before it came out. 100% certain. Cam timing tool will not fit into cam end-slots with crank pinned at TDC unless cams are in correct position.
I think the problem has to be with electronics. Bad ground, failing DME, bad sensor, something.....

AnthonyGS

I’m not certain just trying to think through this with you. I’m no Porsche expert either... just a wrenchhead.

I did recently take the M96 class though and agree on the tools and base cam timing. I’m sure it’s good too.

I really think you may be onto it with a ground issue. The sensors themselves or even the diagnostic port ground or the durametric cable.... Go WoT get just enough vibration the ground is interrupted.... but idling not enough vibration.