A/C problem on a 190E. Can anyone help?

I have a 1987 190E 2.6. My current problem is that the A/C turns off when I'm idle at stop light or parking. I'm not sure if the compressor is turning on and off at that time. It's OK again once I start driving. Hope someone can help.

[Mike Richards]

I'm not a 2.6 expert, but it's merely a 103 motor with a smaller bore than the 3.0 motor I have. I'll try to help.

Start car and turn on A/C. Pop the hood. Looking at the car from the front and more to the right side, start looking downward. Follow the serpentine belt to the A/C compressor which will be the lowest mounted device with a pulley on it that the serpentine belt wraps around. The serpentine belt of course drives a number of devices - power steering, A/C, Alternator, etc.

On the front of the A/C compressor is what's called a clutch. When you activate the system from within the cabin of your car AND all is well, the clutch will engage the compressor and spin.
When the temperature reaches a given level, the system will deactivate the clutch and you'll see the A/C compressor pulley spinning by way of the serpentine belt as it always will, BUT the clutch will no longer be spinning.

If this clutch NEVER engages, the system will not cool. There's quite a long list of things that will cause a vehicles A/C system not to cool, but for starters, the compressor clutch has got to engage so the compressor will begin the flow of refrigerant throughout the system.

I suspect you live in the southern hemisphere. I envy you right now. It would be great to have to turn on the A/C.

Can't wait for summer.

check to see if the auxiliary fan(at the radiator) comes on when you are at a stop. The fan should cycle depending on the pressure in the Hi side of the a/c which will increase without air flow through the cond. Also check to see if your compressor comes on and off rapidly,like everyfew seconds.This is an indication that the system is low on refrigerant.You can check this by looking at the reciever/drier sight glass(round tank with two lines going to it,at the drivers side inner fender behind the head light) . if it looks cloudy the system is low on charge. Be careful around electric fans! the could come on without warning!

[pentoman]

I believe the A/C will cut out if there is a highish load on the engine, or the alternator is not quite putting out enough charge, usually at low RPMs (matching your problem).

The heated rear window will do the same - while stationary, try switching it on. If the light flashes, it has turned itself off because of low battery charge (happened to me when my battery went bad) or bad alternator. Check your battery voltage at idle and post back

good luck