Pinging after car has been driven

Lexus400ride · Lexus Owner Joined: May 27, 2007 Posts: 1

I just bought an 92 SC400 with 125k miles on it. I've driven it for 2 days and both times I went to go park it In my garage, I've heard a rapid pinging sound. The previous owner only drove the car recreationally the last 3 years putting a total of around 7k miles on it in the summer. He stored it during the winter. Could the pinging result from the octane in the gas being lowered due to the car just sitting all winter?

Here is what has been done to it in the last 4 years:
In April of 07:
New Battery Installed
Full Synthetic Oil Change Performed
In August of 06:
New Radiator
Thermostat
New AC Compressor
Rear ABS Sensor
ABS Module
Radiator was replaced
In December of 04:
Catyletic Converters were replaced
Braked Fluid was flushed
Rear Brake Pads Replaced
In March of 03:
P/S Pump Replaced
Timing Belt Replaced
Water Pump Replaced
Serpentine Belt Replaced
AIR Filter replaced
In Sept of 02:
New Exhaust System Installed
New Power Window Regulator Installed

This is all the maint. records read. So I'm thinking the car definitely should be going into the shop within the next week for a full tuneup including: Spark Plugs, Spark Plug Wires, Distributor cap and rotor, as well as Transmission Drain, Rear Diff. Drain, and possibly new front brake pads. Anything else I should have looked into with the car?