Whats happening when you hear engine pinging?

[WH23G3G]

I'm trying to figure out why my engine pings on my daily driver. It's a 98 Ranger, 2.5L. It's got 190,000 miles and the engine pings a lot from 30-50, more persistent when more throttle is needed up hills. It use to have a Superchip in it since it had about 15,000 miles on it and had to use 93 Octane. I've had the chip out for about 10,000 miles and now use 87 Octane. It still pinged with the chip and 93 Octane. I've recently installed the factory replacement plugs, added some new Accel Superstock wires, and it has the Accel Super EDIS coil packs on it too. I've tried two bottles of fuel injector cleaner last night and a couple ounces of Seafoam fed through the vacuum hose. It puffed on the initial start up, but totally clear after that. Could the loss of power up the hill be as simple as a clogged fuel filter, it hasn't been 51,000 miles since I've changed it but it's probably been 30,000. 51,000 is the mileage recommended for fuel filter replacement on this vehicle in the severe schedule. Maintenance has been to the numbers since it was new. Always a bottle of fuel system cleaner every oil change. I guess it should have some carbon deposits by now, but I wouldn't think it would cause that much ping. What is it exactly happening when you hear this pinging, I'm guessing it's the same thing as spark knock too? Does this happen a lot on Chargers with big blocks? Has the gas been alterted?

[Rocky]

I've never used Seafoam before, but when I used the Mopar Combustion Chamber Cleaner on my 93 Grand Cherokee with 210,000 miles my neighbor came over with a firextinguisher because there was so much smoke.  It was like a crop duster for the first couple of blocks before it finally cleaned out.  There is probably alot more carbon in your engine that is causing the pinging.  I'd reccomend using more cleaner before you do anything else.

[41husk]

They use seafoam for marine engines, guys at the lake say theres nothing better, I have never used it.

[Steve P.]

Sound like it's time for a good cleaning. 

I have used BG TOP ENGINE CLEAN with great results.. Be prepared for the fire department to come to your house though.  This stuff does not mess around.. 

Must be used in a well ventilated place..   Mexico would work..