Symptom, loss of horse power (from a stop and going uphill), surge or lunge forward when accelerating (misfire?), Rough idle (occasional knock).
Maintenance, regularly change all filters and fluids, recently had the m.A.F cleaned and changed air filter, spark plugs and wires, oil.
There have been times in the past year or so when the car would crank but not start. Especially when the car was hot. Wait a couple minutes and it would start. Also a couple of times the car would shake fairly hard when started, get up to speed and it was fine.
I have had people tell me anything from a clogged catalytic converter to bad fuel injectors or fuel pump.
Scanned the car last week. No codes showed up. Never had a Check Engine Light.