Cannot find a picture in situ, however this EPC diagram seems to indicate it is on the left rear side of the head cover and is build into the low pressure fuel line (#170.)

As your car is a C218 C216, moving this thread to that forum.

 

Thanks for the Info. I have now found this and connected my tester but not receiving any readings from it?? My tester is a brand new one.

My Car is a C216. It a UK 2014 CL class. Based on the S-class W221.

 

Thanks for the Info. I have now found this and connected my tester but not receiving any readings from it?? My tester is a brand new one.

My Car is a C216. It a UK 2014 CL class. Based on the S-class W221.

Ah sorry my eyes saw CLS550, will get you to the correct forum yet!

Are you taking the pressure reading at idle, or with the key on/engine off?

 

Welcome to the forum @Paulcl500 - please take a moment to read the information on the links below. It explains how to use the forums and update your user profile so that your car's details and your location appear on each post below your avatar. This is good information for others to know when trying to help. It also has good information about how the forums are organized and how to use the search feature:

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