VVT Setup for Mercedes engine

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Hi There,

Seeking for advice on VVT set up for MB engine G4+ Xtreme.

-Engine can start and run. When trying to use VVT function there are both intake and exhaust signal error count.

-offset is correctly set (using cam position function) for both Intake and exhaust cam which are 368 and 121

-Set the CAM control mode in VVT to "User Define" but having an issue with "tooth count" and tooth off set setting for both intake and exhaust. As follow; the cam trigger are "level" type therefore I understand that the tooth count should be "1" as level type create only one pulse per revolution. But the program only allow minimum 2 teeth.

Seeking for you advice.

Thanks and Cheers,

Siri

[Adamw]

Can you attach a triggerscope taken with engine idling please.  

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On 1/18/2021 at 4:59 AM, Adamw said:

Can you attach a triggerscope taken with engine idling please.  

ฤยย

CLK200 tesh 1.pclr

[Adamw]

I think it should work if you use BMW M52 trigger mode and M52 VVT mode.

Note your crank sensor is wrong polarity so you need to swap the +/- wires on the crank sensor.

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@Adamw Thank you. Using M52 Mode work fine. May i ask for a little explanation.

1. For a sake of understanding: In case we found other trigger system which M52 didnot work and the cam sensor is level type. What shall be the tooth count set up.

2. Would G4+ xtream support the CAN protocol for body and Auto trans of Mercedes CLK 200

Thanks a lot for good advice as always

[Adamw]

A single tooth/edge on the cam does not give regular enough cam position updates for satisfactory control of VVT.  This is why user defined mode has a minimum of two teeth.  

The BMW M52 mode is a special trigger mode that uses both the rising and falling edges on the cam sensor so it effectively gets 2 position updates per cam revolution which gives satisfactory information for control of cam position.  It is very uncommon for a VVT engine to have such a low tooth count on the cam wheel like this engine so you are unlikely to be caught out in future.  If there was something special required that we didntr already cover then we would have to code a new trigger mode. 

We have no CAN info for the CLK200 and there are no plans to support it as far as I know, at this stage it is not a popular platform to modify so buying a car to reverse engineer the CAN bus would be difficult to justify.