Need to locate a part R129

[geno]

I need to find the sending unit (I believe it's the air gas mixture sending unit-Mercedes p/n 009 542 68 17.I have the part which is cylindrical with electrical plug in connections on the top and bottom.I have contacted two Mercedes dealers with little help.One dealer said it was located near the air filter on the drivers side,but I can't find it for the life of me.It looks like a simple part to replace if I could find it.
Any help would be deeply appreciated.
The car is a 1994 SL500.

[billwrb]

Tom Hanson at Caliber Motors in Anaheim works miracles. You can search for him in this forum.

[LeaUK]

By your explanation I would say it's either the O2 sensors, these are fitted in the exhaust just before the cat, or the air mass sensor, fitted just beneath the air filter assy.

Ask your dealer to look it up on their EPC (electronic parts catalogue) or buy a copy for yourself - there are several copies available floating around the net

Lea

[geno]

Thank you for the replies.
I looked it up in the parts locator DVD and it said the AIR MASS SENSOR (which I think it is) is located behind the air intake opening.However I still can't locate anything that looks like the part I have.