Greetings,

I'm new to this forum as I just got my first Benz. It is a 1997 E420.
When I turn the aircondition on, there is a loud hissing sound as if it needs to the recharged. the problem is I was not able to find the low pressure valve of the A/C system. Can anyone point me the location of that valve??? Also the driver's side is always wamer than the passanger side regardless the temperature settings, even at the lowest settings.
Appreciate inputs and advices. Thanks

Frank

Low pressure port is in the driver's side at about the center of the fender well. Find the AC line on the side. follow it and it's right there.

Len

For what little I know about a/c units, I do know they need some a/c oil put in with the freon, or you'll fry the compressor.

Thanks for the informations. I looked under the hood and found the valve with a black color cap, I guess this must be it. The line have some sort of distribution coupler made from brass (?) So is this the correct one?
About adding refrigerant with oil, can I just get something from Walmart or Autozone like Interdynamic R134A that already includes oil or do I have to get it from MB dealer
Thanks again

Taking into consideration the cost of replacement parts for this model*, I would not recommend working on it as a diy project. Find someone you can trust with your Benz. (there is a "Good MB shops" section on this site...maybe you can find someone there, or ask around here).

-Larry


*do a search on Fastlane/Partshop (see "buy parts" link above) for A/C part prices.

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09 Jetta TDI
1985 300D