92 240sx running issues

[sean.arnold9012]

hey guys and gals.
ok I might as well start.

I have a 92 Nissan 240sx convertible
the car starts fine. and seems to idle fine also.
runs cool. no codes.

I bought this car with this issue.
if I rev the engine while parked with no load everything seems fine.
but once a pull out to drive it. the car has no power and starts to get engine ping. I tried playing with the timing to eliminate the ping. when I retarded the timing the ping went away, but the power loss was even worse.
if I advance the timing back I get some power back but the pinging returns.

when I bought the car it did have some codes. it had a distributer sensor code. a maf sensor code, I fixed both codes but to no avail.

please ant help or ideas would be appreciated

now lets brain storm and get this solved