Chrysler Repair: car not running, style engine, model body

Question
car will start, but won't sustain and run.  RPM does not go above 500.  Start is awkward and engine is knocking.

Answer
Hi Rick,
What is the year/make/model/body style/engine(L)? We need to get a fault code readout for some direction and that may be available via the ignition key. But I need more details. Is there a history as to how/when this problem began?
Please 'rate/nominate' this answer/me (see the PS below).
Thanks,
Roland