FYI:<P>Ping occurs when there is detonation present in a combustion engine. ( trust me... I know this from experience ) To eliminate ping, fuel enrichment, timing control, and ignition spark must all be carefully tailored. In production run S/C kits, such as the 2nd Generation 4Runner kit, many variables exist which can adversely affect performance, not to mention the outside variables such as weather, vehicle gross weight, other modifications, gear ratios, load ratios, a/f ratios, etc, etc... locking down what causes the pinging is what's important, and importantly hard as well... my experience with pinging in any vehicle has been related to the quality of fuel ( octane ) and the thoroughness of the tuning. a/f ratios, etc... ) Keep this in mind when you start searching for the " common " problem... it's more likely to be a few common problems than one.<P>Jason<BR><P>------------------<BR>Electrical Computeer Engineer<BR>Owner,R&D Development Engineer, Advanced Racing Technologies, LLC<BR>1996 SR5<BR>2nd Gen. TRD S/C<BR>TRD Headers<BR>TRD Exhaust<BR>1.5" Downey Spacers ( front )<BR>2.0" Grizzly Spacers ( rear )<BR>OME Lift<BR>ARB Bull Bar<BR>Warn Winch<BR>Custom Powdercoated Surco Rack<BR>LOTS OF LIGHTS<BR>BIG STEREO