It's not really a "rough" idle, it's more of a lope of sorts. outside the car it sounds like it's idling normally then it will accellerate a tiny bit, just enough to notice it then go back to naormal Idle speed. It hasn't yet dipped below the idle speed..only when I'm low on diesel.

I don't run WVO or Bio...yet..

how can I tell if I have algae in my tank? I think the last time I replaced that pre filter was last oilchange which was November 1st. Secondary was changed earlier this summer. It doesn't really bothe me at all, it only does it when it's cold. i'm just curious, unless of course it's a symptom of some catastrophic impending IP failure...

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RIP: 80 300SD
RIP: 79 450SEL
2002 E430 4matic (212,000km)
2002 ML500 'sport'

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