Hi, I have a 88 300CE which stalls intermittently when it is coming to a stop or at a stop with rough idling ONLY before the stalling. I have read many posts regarding possible causes and fixes including one post suggesting that a bad distributor cap can also cause it. I remember that the problem of stalling started around after Pepboys changed my cap and rotor because I couldn't get my car started. I am not quite sure the exact timing. So I would like to confirm with you guys is it possible for a bad cap or/and rotor to cause the stall with forewarning rough idle? In addition, how can I confirm that this is exactly the cause of the problem before I purchase the new parts? Thanks very much

Rick