Variocam Issue?

[freserf]

What tool ... that is reasonable would be best to look at the signals? I only have MBII iCarsoft tool that I use with my Benz. I am able to read live data, but not much ... o2 sensors, TPS, fuel demand, rpm ... it also has o2 sensor tests that seem to be good. I guess I will find the computer (DME) and check connections and double check for bad or rubbed wires.

[blue62]

Originally Posted by freserf

What tool ... that is reasonable would be best to look at the signals? I only have MBII iCarsoft tool that I use with my Benz. I am able to read live data, but not much ... o2 sensors, TPS, fuel demand, rpm ... it also has o2 sensor tests that seem to be good. I guess I will find the computer (DME) and check connections and double check for bad or rubbed wires.

If you could get something like the Durametric or a Foxwell that reads cam deviation or cam angle. one of those would work.
I have both. on either scanner I can look at Camshaft deviation on each bank.

I can also look at actual cam angle while the car is running so I can compare one bank to the other to see if they are close to each other or are the numbers way different from one bank to the other.
That is what I would want to look at in your case with the sensor testing good.

If your tool is able to test the cam position sensor and it tests good then it is probably ok. I believe the scanner is reading what the DME sees.

[freserf]

Which Foxwell reader?

[blue62]

I have the Foxwell NT520 PRO

[freserf]

Here is another symptom maybe you can help me with ... I am still not quite sure how this variocam system works. When are the solenoids activated? Does the actuator float under oil pressure when the solenoid is not activated? The reason I ask is this ... I just unplugged bank1 solenoid and now I can rev and idle without the timing chain noise as I experienced earlier. But, I still have bank1 misfires on all cylinders without the P0341.

I'll probably swap coils this weekend to rule them out for the misfire.

I am guessing that the solenoids are active from engine on to about 2800 rpm's or when demand is high? I read somewhere about the basics of the variocam system, but nothing detail related to when it is active.

Thanks for the input ... it is always helpful to learn from others.

[blue62]

Originally Posted by freserf

Here is another symptom maybe you can help me with ... I am still not quite sure how this variocam system works. When are the solenoids activated? Does the actuator float under oil pressure when the solenoid is not activated? The reason I ask is this ... I just unplugged bank1 solenoid and now I can rev and idle without the timing chain noise as I experienced earlier. But, I still have bank1 misfires on all cylinders without the P0341.

I'll probably swap coils this weekend to rule them out for the misfire.

I am guessing that the solenoids are active from engine on to about 2800 rpm's or when demand is high? I read somewhere about the basics of the variocam system, but nothing detail related to when it is active.

Thanks for the input ... it is always helpful to learn from others.

If I understand the system correctly: When the solenoid activates it exposes oil ports which allows oil pressure to force the Variocam actuators outwards against the cam chains. Thus changing cam timing. I think this happens at around 1500-1800 RPM then it kicks back out around 5000 RPM.

If you do a search here on the forum I think you could find a more detailed explanation then the very brief one I have given. You should also be able to find the precise RPM range that the system operates in as well.

[freserf]

Thanks ... appreciate your feedback.

[freserf]

Just wanted to update what tool I chose ... I ordered the Foxwell NT520 Pro that says it has been updated to the NT530. I mainly need it now to reset the airbag light ... I made the newbie mistake of hooking up the battery with the passenger seat out of the car ... thanks for the recommendation.