Engine shudders intermittently when idle, should I be concerned?
I have an 09 Mz3 I Sport automatic transmission about 40k miles all stock no upgrades (at least by me, prior owner was a fleet).
The car drives great and has never caused an actual problem but there is some strange behavior when idle that Iíve noticed that Iím not used to (though this is my first car) or havenít seen in any other cars Iíve driven.
Just after coming to a stop at a red light I will hear a faint sound like an electric motor moving something around, I think it is coming from the engine compartment, anyone know what this is?
Also when idle the engine goes through a cycle of being quiet, vibrating a little bit, then shuddering and suddenly going quiet (canít feel anything anymore), it feels like it just stalled out but I know it didnít because the whole thing keeps repeating, I canít notice it when music is playing which is almost all the time. The engine never actually stalls and there is no CEL. It idles at well under 1k RPM.
p.s. also, the RPM needle doesn't seem to move at all when idle, just sits about where I'm guessing it should.
Should I have it looked into or does the description fit closely enough with failures like engine mount of purge valve?
[size=6pt]Mods: 17x7.5 rims w/ Conti DWS tires | 4 75W kicker speakers | Memphis 300W amp | full size spare | BC Condenser kit w/ extra grounds | CS SRI w/ box | timing advance | upgraded horn | CS LED kit | Axela badge | alu pedals | Momo shift knob | Alu fuel door | footwell LEDs | VTCS delete | TB coolant bypass | L fog light vent | bi-xenon HB/LB | HID fogs | SB LED turn sigs | LED DRLs | LED reverse lights | painted foglight trim | LED tail lights | LED reflectors[/size]