Originally Posted by retmil46

X2 on the ALDA. On my two 87's, both were sluggish when I first got them - and I never had to touch the ALDA on either one to cure the sluggishness and make them live up to their "rocket ship" nickname - matter of fact, on one of them, the ALDA is still "virgin" with the original factory cap.

I just got a copy of the W124 Service Library and started walking thru all the checks and adjustments in the FSM - throttle cable idle and full stop, throttle linkage, tranny feedback cable and vacuum signal, vacuum control valve, vacuum lines, sensor lines, resistor cap idle setting, etc, etc - once all the basics were set back to rights after twenty-some-odd years, there wasn't any need to mess with the ALDA.

Quick check you can do to verify the aux water pump is toast - start the car and let it run until it's at some semblance of full coolant temp. Set the climate control for max heat, blower in auto, and while still idling put it in Defrost mode. If you don't see the coolant temp gauge drop like a rock by at least 5 to 10 C after at least 15 to 20 seconds, the aux water pump has went bye-bye.

Aux water pump is also important from another standpoint - it's nearly effin impossible to get all the air vented from the heater circuit after a coolant change with a nonfunctional AWP.

What's your oil pressure running at cold and hot idle? If I remember correctly, minimum spec per the FSM is around 1 bar at hot idle. Even if it's getting toward the low end at hot idle, as long as it zooms back up as soon as you give it some throttle it's still healthy enough for quite some time to come.