Variocam thoughts and questions

[Homeoboxter]

Originally Posted by sfkjeld

Ok, I don’t get this. Just received my new OBDII scanner yesterday. I cleared the 3141 error code (Camshaft Adjustment Bank1 below limit value) that threw the CEL. I cleared the code with the engine running. The moment the CEL cleared, the engine idled down maybe a hundred rpm. In addition, when I start the car after the CEL was cleared, the car does not really “rattle” the 1st second or two after starting as it had. Other than this anomaly, it runs normally otherwise.

Why does the car start and idle differently with the CEL on than off? Why would the chain “rattle” be different? Is that the nature of the 3141 code?

Sounds interesting. What I can think of is that your solenoid got stuck in one position and clearing the code made it go back to where it should be at low rpms. But i`m just guessing. Did the CEL come back? You may wanna ask this question in a separate thread, perhaps more folks will chime in with knowledge about these error codes.

[sfkjeld]

Originally Posted by Homeoboxter

Sounds interesting. What I can think of is that your solenoid got stuck in one position and clearing the code made it go back to where it should be at low rpms. But i`m just guessing. Did the CEL come back? You may wanna ask this question in a separate thread, perhaps more folks will chime in with knowledge about these error codes.

No, I think are right. Thank you. Yes, the CEL did return a few days later. I went through the same process but this time, the idle wasn’t really rough to start with. I cleared the CEL and there was absolutely no change in the idle. So To your point, the cam may not have been in the wrong position.

I have an appointment to bring the car into the shop next week to address the cam issue. Am guessing it is the solenoid anyway.

[sfkjeld]

Originally Posted by sfkjeld

No, I think are right. Thank you. Yes, the CEL did return a few days later. I went through the same process but this time, the idle wasn’t really rough to start with. I cleared the CEL and there was absolutely no change in the idle. So To your point, the cam may not have been in the wrong position.

I have an appointment to bring the car into the shop next week to address the cam issue. Am guessing it is the solenoid anyway.

Brought my car to a relatively high end Porsche shop, tho they seem to be more about racing than repairing old Boxsters. Anyway, the car was throwing a 1341 CEL. After they replaced the actuator, they found the car was still throwing the 1341. Their explanation is that when the actuator failed, it fried the “computer”. So they are now replacing the “computer”. They said it is a known problem. I find this a little hard to believe. Anyone with any experience with this? As many report with the dreaded 1341 CEL, the car ran great when I brought it into this shop.

[blue62]

Originally Posted by sfkjeld

Brought my car to a relatively high end Porsche shop, tho they seem to be more about racing than repairing old Boxsters. Anyway, the car was throwing a 1341 CEL. After they replaced the actuator, they found the car was still throwing the 1341. Their explanation is that when the actuator failed, it fried the “computer”. So they are now replacing the “computer”. They said it is a known problem. I find this a little hard to believe. Anyone with any experience with this? As many report with the dreaded 1341 CEL, the car ran great when I brought it into this shop.

Did the shop verify that the cams were out of time before they replaced the actuator?
Did they record and tell you by how many degrees the cams were out of time?
Pretty simple to do.

Did they show you the faulty actuator and explain the fault with it?

If a DME -ECU- computer is fried how does it throw a code?
Or keep the car running??

Just a few questions that enter my mind

[sfkjeld]

Originally Posted by blue62

Did the shop verify that the cams were out of time before they replaced the actuator?
Did they record and tell you by how many degrees the cams were out of time?
Pretty simple to do.

Did they show you the faulty actuator and explain the fault with it?

If a DME -ECU- computer is fried how does it throw a code?
Or keep the car running??

Just a few questions that enter my mind

No mention of cams being out of time. Wouldn’t the car run differently if they were? And yes, I don’t get how a fried computer would allow the car to run completely normally. Much less still able to throw the same 1341 code with the CEL.

[Homeoboxter]

Originally Posted by sfkjeld

No mention of cams being out of time. Wouldn’t the car run differently if they were? And yes, I don’t get how a fried computer would allow the car to run completely normally. Much less still able to throw the same 1341 code with the CEL.

I think when you get this code, that can also be because the two actuators are not running syncronously, one is working while the other is not, which will result in a difference in timing between the two intake camshafts, but only in a specific rpm range. This does not mean that your engine won`t run. It will, just not ideally. Correct me if I`m wrong. This "fried computer" thing sounds puzzling. It`s hard to imagine that the actuator and the computer both die at the same time... Did they show you the faulty actuator?

[blue62]

Originally Posted by sfkjeld

No mention of cams being out of time. Wouldn’t the car run differently if they were? And yes, I don’t get how a fried computer would allow the car to run completely normally. Much less still able to throw the same 1341 code with the CEL.

Your cams can be out of time and the engine will still run fairly well.
Depends on how far out of time they are.

If you have one actuator not working your cams can still be in time until around 1500 RPM when the actuators are supposed to actuate. Then the cams on one bank will be out of time. Then the actuators kick back out around 5000 RPM so the cams will again be in time.

If the shop can not tell you if the cams were out of time and by how much before they replaced the actuator.
And if they are not showing you the faulty actuator and what the issue was with it.
That they charged you big money and didn't fix anything
Also now they want to replace the computer.
For more money.

Sounds to me like
1. they don't have a clue as to what they are doing.
2. they are taking you for a ride.

[sfkjeld]

Originally Posted by Homeoboxter

I think when you get this code, that can also be because the two actuators are not running syncronously, one is working while the other is not, which will result in a difference in timing between the two intake camshafts, but only in a specific rpm range. This does not mean that your engine won`t run. It will, just not ideally. Correct me if I`m wrong. This "fried computer" thing sounds puzzling. It`s hard to imagine that the actuator and the computer both die at the same time... Did they show you the faulty actuator?

The shop claims that when an actuator fails, it often “fries” the Computer. But as I say, this car runs perfectly. Low rpm and high rpm. They are installing a used computer today and presumably the car will then stop throwing the 1341 CEL. I will be surprised if that works. I have asked for all the replaced parts so will receive the Old bank 1-3 actuator and the “fried” computer.

[sfkjeld]

Originally Posted by blue62

Your cams can be out of time and the engine will still run fairly well.
Depends on how far out of time they are.

If you have one actuator not working your cams can still be in time until around 1500 RPM when the actuators are supposed to actuate. Then the cams on one bank will be out of time. Then the actuators kick back out around 5000 RPM so the cams will again be in time.

If the shop can not tell you if the cams were out of time and by how much before they replaced the actuator.
And if they are not showing you the faulty actuator and what the issue was with it.
That they charged you big money and didn't fix anything
Also now they want to replace the computer.
For more money.

Sounds to me like
1. they don't have a clue as to what they are doing.
2. they are taking you for a ride.

Yes, kind of what I am thinking. Both #1 and #2. Once they replace the computer and the car is still throwing the 1341 CEL, it’ll be interesting to hear plan C.

This is a high end shop. Between the race cars, turbos and both newish 911’s And air cooled 911s. But I’ve never seen Boxsters in that shop. When it comes to the vario cam system for 986s, is it the same as 996s? I assumed it was.

[blue62]

Originally Posted by sfkjeld

Yes, kind of what I am thinking. Both #1 and #2. Once they replace the computer and the car is still throwing the 1341 CEL, it’ll be interesting to hear plan C.

This is a high end shop. Between the race cars, turbos and both newish 911’s And air cooled 911s. But I’ve never seen Boxsters in that shop. When it comes to the vario cam system for 986s, is it the same as 996s? I assumed it was.

Sorry I am not familiar with the 996 so I would not know.
I do know that they only used the twin actuator style in the Boxster from 1997-2002.
In 2003 they went to a different method of varying cam timing.

Keep us posted on the outcome.
Always interested on end results.

[JFP in PA]

Originally Posted by sfkjeld

When it comes to the vario cam system for 986s, is it the same as 996s? I assumed it was.

Both the 996 and the 986 used similar VarioCam systems, the only difference was what year the Boxster when to the later VarioCam+, which was after the 996 had changed over.

[sfkjeld]

Originally Posted by blue62

Sorry I am not familiar with the 996 so I would not know.
I do know that they only used the twin actuator style in the Boxster from 1997-2002.
In 2003 they went to a different method of varying cam timing.

Keep us posted on the outcome.
Always interested on end results.

Just picked up the car. Turned out the new computer did not clear the CEL as they thought. At least they Didn’t charge me for the new computer. What they did do was replace the cam solenoid and replaced some wiring they thought could be causing the 1341 CEL. They said the oil pressure to the actuator is moving the cam now. But not to spec. That said, the car still passed the CA smog test. So they asked me to drive it 500-1000 miles then they wanted to flush the engine thinking it might clear a plugged oil gallery. They also changed the oil and said the oil filter was clean.

30 miles after picking up the car, the 1341 CEL returned. So I guess I’ll do the engine flush, but seems a long shot. Otherwise, I may just drive the car with the CEL. Hopefully I can clear the CEL and it will still pass smog next year.

[blue62]

Originally Posted by sfkjeld

Just picked up the car. Turned out the new computer did not clear the CEL as they thought. At least they Didn’t charge me for the new computer. What they did do was replace the cam solenoid and replaced some wiring they thought could be causing the 1341 CEL. They said the oil pressure to the actuator is moving the cam now. But not to spec. That said, the car still passed the CA smog test. So they asked me to drive it 500-1000 miles then they wanted to flush the engine thinking it might clear a plugged oil gallery. They also changed the oil and said the oil filter was clean.

30 miles after picking up the car, the 1341 CEL returned. So I guess I’ll do the engine flush, but seems a long shot. Otherwise, I may just drive the car with the CEL. Hopefully I can clear the CEL and it will still pass smog next year.

Well that sucks.
Hard to give any further advice without having the car at hand.
Giving advice over the net is kind of a crap shoot at best.

[Homeoboxter]

Originally Posted by sfkjeld

Just picked up the car. Turned out the new computer did not clear the CEL as they thought. At least they Didn’t charge me for the new computer. What they did do was replace the cam solenoid and replaced some wiring they thought could be causing the 1341 CEL. They said the oil pressure to the actuator is moving the cam now. But not to spec. That said, the car still passed the CA smog test. So they asked me to drive it 500-1000 miles then they wanted to flush the engine thinking it might clear a plugged oil gallery. They also changed the oil and said the oil filter was clean.

30 miles after picking up the car, the 1341 CEL returned. So I guess I’ll do the engine flush, but seems a long shot. Otherwise, I may just drive the car with the CEL. Hopefully I can clear the CEL and it will still pass smog next year.

That must be disappointing, sorry to hear When I rebuilt my heads I flushed the actuators with fresh oil a couple times with a syringe. The oil that came out didn`t look good. I can imagine that if the solenoid is not working for a while the old oil inside the actuator gets cooked and the small oil passages get clogged, so maybe it works out after a couple more hundred miles. Did you confirm the solenoid was faulty?

[sfkjeld]

Originally Posted by Homeoboxter

That must be disappointing, sorry to hear When I rebuilt my heads I flushed the actuators with fresh oil a couple times with a syringe. The oil that came out didn`t look good. I can imagine that if the solenoid is not working for a while the old oil inside the actuator gets cooked and the small oil passages get clogged, so maybe it works out after a couple more hundred miles. Did you confirm the solenoid was faulty?

Thanks. I asked the shop whether the solenoid was bad. They concluded it must have been because it was not moving the actuator at all when they first tested it. After replacing, it does move but not to spec. They referred to it as “slow”.

Hence they want to do this engine flush in the hopes of clearing an oil gallery to increase oil pressure in the actuator. Again, that sounds like a Hail Mary. But after your syringe experience, maybe the flush might clear out something.

Must say, I am stunned at how little difference the vario cam seems to make. If as they said, it wasn’t working at all on bank 1-3 when I brought it in, and it’s not working well now, why does the car run so well? I can’t tell the difference. Seems like a lot tech for not much performance.

[Homeoboxter]

Originally Posted by sfkjeld

Thanks. I asked the shop whether the solenoid was bad. They concluded it must have been because it was not moving the actuator at all when they first tested it. After replacing, it does move but not to spec. They referred to it as “slow”.

Hence they want to do this engine flush in the hopes of clearing an oil gallery to increase oil pressure in the actuator. Again, that sounds like a Hail Mary. But after your syringe experience, maybe the flush might clear out something.

Must say, I am stunned at how little difference the vario cam seems to make. If as they said, it wasn’t working at all on bank 1-3 when I brought it in, and it’s not working well now, why does the car run so well? I can’t tell the difference. Seems like a lot tech for not much performance.

Well, the solenoid just operates a valve that controls oil flow within the actuator. It still can be totally fine if the actuator is bad, or the oil passages are blocked. It’s not too parsimonious to replace a $500 part without making sure it’s faulty. If you have the solenoid you can easily test it with a battery.

[sfkjeld]

Originally Posted by Homeoboxter

Well, the solenoid just operates a valve that controls oil flow within the actuator. It still can be totally fine if the actuator is bad, or the oil passages are blocked. It’s not too parsimonious to replace a $500 part without making sure it’s faulty. If you have the solenoid you can easily test it with a battery.

thank you. Could they have tested the solenoid before replacing it? They also claimed a failed actuator is extremely rare.

[blue62]

Originally Posted by sfkjeld

thank you. Could they have tested the solenoid before replacing it? They also claimed a failed actuator is extremely rare.

A solenoid is just an electromagnetic device.
It could have been tested with a multimeter via back probing the wiring connections.
Also the function of the actuator can be tested with a OBDII scanner that has test functions.
With my $175.00 Foxwell scanner I can trigger my actuators then not only hear the difference in how the engine runs.
I can also see the cam timing change and by how many degrees.
Very simple tests that verify function.

[sfkjeld]

Originally Posted by blue62

A solenoid is just an electromagnetic device.
It could have been tested with a multimeter via back probing the wiring connections.
Also the function of the actuator can be tested with a OBDII scanner that has test functions.
With my $175.00 Foxwell scanner I can trigger my actuators then not only hear the difference in how the engine runs.
I can also see the cam timing change and by how many degrees.
Very simple tests that verify function.

Thank you, very interesting. I recently purchased a Foxwell scanner, probably at your suggestion. I’ve used it only to clear the CEL. Are you able to see the timing change on the scanner?

[blue62]

Originally Posted by sfkjeld

Thank you, very interesting. I recently purchased a Foxwell scanner, probably at your suggestion. I’ve used it only to clear the CEL. Are you able to see the timing change on the scanner?

I can on my scanner.
It is the Foxwell NT520 Pro

I went out and hooked it up to my 2000S so I could refresh my memory on how I do it.
I will attempt to talk you through it.

Hook up the scanner
Go to the Porsche program and hit enter.
Go to manual selection and hit enter.
Go down to 986 Boxster/Cayman hit enter.
Go to Diagnosis hit enter.
Go to control units hit enter.
Go to DME (its the top choice on my scanner) hit enter.
Go down to actual values hit enter.
Go to all data hit enter.
Now you should be looking at a list of all the data the DME sees.

With the car running you can watch all this data under different driving conditions.
You can watch all the data the DME sees in real time. You just have to learn what your looking at and what it means.
I have hooked mine up and watched various data over a 320 mile run several times.

Now go down till you see camshaft deviation for each bank
Below that is actual camshaft angles.


so if your at idle watching camshaft angle you should see changes when your Variocam timing actuator kicks in. I think that is around 1500 RPM. then I kicks back out around 5000 RPM. Not positive on those RPM's but I should be in the ballpark.
You can graph it with the graphing feature and see changes over a short period of time.
I think you can also Data log with this scanner but I have never tried it.

Now You can back out to where you found actual values and go down to
Drive links active.
Hit enter
Now you can activate your fuel injectors and your Variocam timing Actuators.
sort of a test mode.
You will hear and feel the difference when you activate the injectors or the actuators with the engine running.
Now simply activating them does not tell you that everything is within spec. but it will tell you if they function, or not.

So that is how it works with my scanner on my 2000S

Hope this helps
Let me know how you go