'Re-boot' a W124 200E?

[tom7035]

Several months ago I acquired a '93 vintage 200E with the 111 16v engine. I knew it to have an idling problem in that it would not idle on cold start-up and required light throttle for around 30 seconds or so, before it would continue to idle on closed throttle, at around 500 to 600 r.p.m. When warmed up it idled at 1000 r.p.m., which was a touch on the fast side, but neither of these problems were much more than an inconvenience. Being a newcomer to the Mercedes marque, I made some enquiries re. corrective measures required and items like 'throttle body' and 'airflow mass sensor' etc. were suggested. After picking myself up from the floor when I costed said items and, being a pauper, I asked myself 'what on earth have I done!' Needless to say I decided I would just have to put up with it as is, as it did run sweetly enough regardless. After another month or so the remote locking/alarm system inexplicably ceased to function. I tried all the locking and unlocking and waiting ten seconds and all of the stuff the manual said to do, but nothing. I persevered simply using the key in the old-fashioned way. However, a couple of weeks ago I was carrying out some routine maintenence, spark plugs, oil change, filters etc., and dropped a small part down behind the battery into the battery tray in the engine compartment. I had to remove the battery to recover the item and lo and behold when reconnecting it the alarm siren blasted out. (still have the bump on my head, hadn't fully raised the bonnet!) I checked the remote locking/alarm function and all worked perfectly. Even more surprising, after lying unused for two days, the engine idled at a near-perfect 750 - 800 r.p.m. on cold start-up and even after warm-up, remained consistent! It was just as though I had 're-booted' the thing! Has this sort of thing happened to anyone else (or are you now going to try it!!) Can someone please explain to me why this has happened, or does somebody UP THERE really like me? Tom.