Isolating a single variable is often very difficult. There are obviously many interdependent variables in play and, to make matters more complicated, multiple, marginally functional causes can stack minor defects together to create big issues. This is especially true with older, worn machines (which is part of what makes preventive maintenance so important). We'll never know the cause(s) of your particular problem until you get it fixed. Even then, you may only have addressed a sufficient number of the contributing factors involved.
Last edited by Reasoned1; 06-29-2018 at 12:11 PM.
2004 BMW 330i ZHP (52k miles), Jet Black with black leather, MFactory LSD (3.38) with Z4 cover, 18"x8.5" ET38 APEX Arc-8's (Anthracite) with 245/40 Michelin PSS', Koni Sports with factory springs and front and rear reinforcement plates, Shark Injector, Corsa TSE3 cat-back exhaust, TMS under-driven pulleys (water & steering), CDV delete, TMS CF strut brace, K&N CAI, GAS DISA rebuild, TMS pedals, Wheelskins steering wheel cover, roller tray center console, black-out grilles, and WeatherTech mats