Well the search and I are not getting along. Google'd too. I can not find what the AC high/low pressures should be for my car, 99 E300. Can someone please let me know?

Thank you for your help.

I wish I could help. Have you called the dealer near you?

http://www.ackits.com/aacf/ptchart.cfm

The pressure chart is in the FSM. Of course, there is no one "correct" set of pressures, as they depend on a whole host of temperature readings.

Note that we have a TXV system, and a pressure check is only used to confirm proper operation. You cannot properly charge a TXV system by pressure alone; you must add refrigerant by weight.

CCOT systems (cycling compressor, orifice tube) are much more stable over various conditions, and pressure readings are more accurate at determining refrigerant levels. But we don't have a CCOT system.

Run the system at 1500 RPM, windows down, recirculate ON, fan on HIGH, temperature controls on LO. Measure the pressures (once things stabilize) and post these, as well as the temperature in front of the condenser, the temperature at the vent, the temperature in the cabin, and the relative humidity in the cabin. Also post all current-sensor readings available at the climate-control pushbutton unit. Then I (or someone else) can look it up in the chart.

Make note of whether your auxiliary fan is running. Both sides.

http://www.eclassbenz.com/acdiag

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96 E300d

Thank you for guidance Matt. We got it charged up and blows so cold now I have to turn up the temps.