On my 1994 Mercedes E320 wagon,I am getting low idling so low it kills the engine. Troubleshooting on the DM Self Test Diagnostic Module (16 pin) indicated a code 6 meaning Idle speed control faulty. That is the only code showing using the DM.

When I use the code reader to retrieve the codes on the individual pins, the code reader shown these results:

Pin 6, code 9, SRS malfunction indicator lamp (A1e15) or time limit for DTC readout /erasing e

Pin 8, code 8: Idle speed control (ISC) system at upper or lower control stop or CC or EA indicates "limp home" mode

Pin 8, code 13: O2S (Lambda) control system operating at rich or lean limit

Pin 14, code 2: EA/CC/ISC control module (N4/1) or Safety contact switch (M16/1s1) or Stop lamp switch or Cruise control switch or Actual value potentiometer or Starter lock-out/back-up lamp switch or engine speed signal or vehicle speed signal or closed throttle position switch or safety relay in EA/CC/ISC control module.

In addition, my cruise control does not work, either.

I removed the throttle body and sent to repair shop. In addition, I ordered new valve cover gasket replacement, new throttle body gasket and throttle bottle cover to intake manifold. While I am waiting for the replacement parts to arrive, I wonder if I should get new 6 coils to plug boots, 6 new spark plug wires and 6 new spark plugs? When I bought the 1994 Mercedes E320 last year, very little history of the Mercedes was given to me. Since I already removed the throttle body, reasonance valve and about to remove the valve cover, do I, might as well, replace 6 spark plugs, 6 coils, 6 coils to plug boots, 6 spark plug wires as new? That way, the engine will have proper idling, eliminating some if not all, idling issues? Any other parts need to be replace as well that I am not aware of? How do I know and/or can tell if the 6 coils, 6 coil to plug boots, the 6 spark plug wires and 6 spark plugs are good that I have on now? Just thinking out loud. In addition, I did some research on the type of spark plugs and found Bosch F8DC4 as the only kind spark plug to use, no exception. Comments, anyone?