I have a 2007 Scion tC, ~122,000 miles, manual, with a PO335 code that sometimes reads as intermittent. It has shown up and disappeared several times. While accelerating it will "stutter" or "jump" while some of the lights on the dash will flicker like the oil or ABS light. Once it starts to act up the check engine light(PO335) will usually appear, but it will still stutter while there's no check engine light, however considerably less. It happens in both higher and lower gears but happens more in the lower gears. I've already replaced the crankshaft position sensor, alternator, spark plugs, and battery. I also replaced the valve cover gasket since I noticed there was oil in the spark plug wells while inspecting them. The new position sensor is not damaged or defective. My mechanic can't find a strong indication of a single cause and recommended me to bring it once it happens more often. It happens about every other day. It's frustrating since it makes driving a lot less enjoyable and I don't know how to fix it. Thank you.