W124 cruise control amp, is this the culprit?

[amg280]

Quick question. Im pretty sure this is caused by an amp going bad, but wanted to run it through you guys for good measure. My cruise in my 93 300D works flawlessly. However, when going down a slight slope, the car will jerk back and forth. You can feel and see the accel pedal going in and out, jerking the car. As soon as the road levels out, its good to go.

Amp?

All the linkages look good under the hood, and like i said, on flat ground or up a hill, it works perfect.

thanks for any advice. Should I source a used one? Reman? Resolder mine?

[BlubBlub]

No advice to offer, just adding my issue with the same car, a '93 W124 300D 2.5 Turbo. Cruise will engage for a few seconds, then falls out of cruise... Is this the amp or the actuator acting up?

Would also like to know where the amp is located on this car. One guy tells me it's under the passenger's side floor kickplate, another says that on the diesels it's tucked up under the dash, like in older models...