Sometimes when I start it up, in the first 10 sec or so I might get these 'jolts'. The jolt lasts just a moment, and briefly shakes the entire car. Somewhat violent, you might say. Feels like it's coming from the engine compartment. Maybe a pump clogged and fighting through something?

I very often get 0 jolts upon start up. Sometimes I get 1 or 2 jolts. Today, I got 6 or 7 and the car idled very roughly; shut it down, started it back up and it smoothed out.

Fuel filter is old, and diesel purge has been pumping through its veins for a while (and is currently in right now too). Power steering is intermittent.

What worried me is the car idled so roughly today when I got 6 or 7 jolts... The most I've ever gotten. Any ideas?