Variocam failure?

[Paul Grainger]

I suspect that variocam is not working properly on my 1999 996 C4 6-speed coupe.

The car drives 'ok', no fault codes are reported but Durametric indicates no cam variance on bank 2. Is this normal? Indications show that bank 1 cam angle varies as the car is revved, but not bank 2 (the readings show zero).

If this is a problem, what is the likely cause? Is it something that I could undertake myself?

It might be my imagination, but the car seems to have less power at low RPM. Maybe I am imagining this, but there is a massive surge of power at about 4500rpm.

Thanks in anticipation of a helpful reply!

Paul G

[White987S]

Did Porsche have Variocam in 1999?

[PTEC]

Chances are if you have no faults then every thing is working ok. My only guess as to why you are not getting a reading is Durametric is a generic tool and does not have full functionality of the actual Porsche systems tester (PIWIS). I have never seen a bad solenoid in the early style cars but I have seen a few go bad in the later style (02 and on). In the later cars when they go bad, the car will not idle at all. It run terribly rough and will die sometimes. The car will have a flashing check engine light and usually at least five faults in the DME for misfires and cam timing.

And yes the first boxsters had variocam and if I'm not mistaken the 968s had it as well.

Edited April 16, 2007 by PTEC

[RFM]

Variocam banc 2 have got no pick up for the diagnose system on MY 1999.

[1999Porsche911]

Variocam banc 2 have got no pick up for the diagnose system on MY 1999.

It sure does. Both banks are monitored the same.

[Paul Fraser]

FWIW had both the variocam solenoids done on my 1997 Boxster 2.5 -- are they the same as the early 996?

[PTEC]

Variocam banc 2 have got no pick up for the diagnose system on MY 1999.

It sure does. Both banks are monitored the same.

Actually, hes right. I just noticed both he and the original poster both have ROW cars. For whatever reason, ROW cars do not monitor the bank 2 intake cam, only US cars do.

Edited April 20, 2007 by PTEC

[1999Porsche911]

Variocam banc 2 have got no pick up for the diagnose system on MY 1999.

It sure does. Both banks are monitored the same.

Actually, hes right. I just noticed both he and the original poster both have ROW cars. For whatever reason, ROW cars do not monitor the bank 2 intake cam, only US cars do.

So, are you saying there is not a cam sensor on bank 2 for the ROW engines? That's strange.

[tholyoak]

ROW cars do not have to meet OBDII standards and thus only have one cam sensor, this is all that is needed to control the variocam.

Todd

Variocam banc 2 have got no pick up for the diagnose system on MY 1999.

It sure does. Both banks are monitored the same.

Actually, hes right. I just noticed both he and the original poster both have ROW cars. For whatever reason, ROW cars do not monitor the bank 2 intake cam, only US cars do.

So, are you saying there is not a cam sensor on bank 2 for the ROW engines? That's strange.

[1999Porsche911]

ROW cars do not have to meet OBDII standards and thus only have one cam sensor, this is all that is needed to control the variocam.

Todd

Variocam banc 2 have got no pick up for the diagnose system on MY 1999.

It sure does. Both banks are monitored the same.

Actually, hes right. I just noticed both he and the original poster both have ROW cars. For whatever reason, ROW cars do not monitor the bank 2 intake cam, only US cars do.

So, are you saying there is not a cam sensor on bank 2 for the ROW engines? That's strange.

I wasn't even think emissions. I would think that they would still need a sensor to reportng the position of the cam since the controls are completely seperate for each bank. Since timing is electronically controlled, they have to have some sensor on both banks in order to determine valve lift. Parts list shows one sensor for each bank, even on ROW.

[tholyoak]

If you look at the factory wiring diarams, the diagnosis section in the factory manual or the PST2 output of a DME with a ROW program there is no bank 2 cam sensor on non-OBDII cars.

The hall sensor is only used to detect ignition TDC for cylinder #1 for ignition, the sequential fuel injection and knock regulation. It is only used to diagnose the Variocam function (as the signal should advance and retard due to the state of the variocam actuation). It would appear that the necessary info for both banks can be caluculated in the DME from one sensor output. Currently, I am running a ROW program on my 3.6 using a 3.4 DME for a number of reasons, and it only recognizes the sensor input from the bank 1 sensor eventhough both are present.

Todd

Edited April 22, 2007 by tholyoak

[JoostE]

I suspect that variocam is not working properly on my 1999 996 C4 6-speed coupe. The car drives 'ok', no fault codes are reported but Durametric indicates no cam variance on bank 2. Is this normal? Indications show that bank 1 cam angle varies as the car is revved, but not bank 2 (the readings show zero). If this is a problem, what is the likely cause? Is it something that I could undertake myself? It might be my imagination, but the car seems to have less power at low RPM. Maybe I am imagining this, but there is a massive surge of power at about 4500rpm. Thanks in anticipation of a helpful reply! Paul G

Hi Paul, what was the final conclusion for you car ? Were there problems with the variocam ?

[JFP in PA]

I suspect that variocam is not working properly on my 1999 996 C4 6-speed coupe. The car drives 'ok', no fault codes are reported but Durametric indicates no cam variance on bank 2. Is this normal? Indications show that bank 1 cam angle varies as the car is revved, but not bank 2 (the readings show zero). If this is a problem, what is the likely cause? Is it something that I could undertake myself? It might be my imagination, but the car seems to have less power at low RPM. Maybe I am imagining this, but there is a massive surge of power at about 4500rpm. Thanks in anticipation of a helpful reply! Paul G

Hi Paul, what was the final conclusion for you car ? Were there problems with the variocam ?

You are replying to a six year old posting...................