TBI 454 pinging under load (FIXED) UPDATE in OP

[CJ7365]

Just returned from a 1400 mile trip, I was getting some pinging going up hill, if I let off the throttle would subside.  Still averaged around 7.8 MPG @ 60-65m.p.h.

I had just replaced the plugs with A/C delco rapid fire before I left, when I got home tonight, pulled right rear plug, looked fouling/black, other plugs where nice and brown.

I replaced that plug and did a test drive, still noticed a little pinging not as bad though.

Should I go back to the stock copper plugs?

Wires?

Never had pinging before until I changed plugs, so I don't want to mess with the timing yet

is anyone running the Rapid FIre plugs?

Will do some more TS tomarow

******UPDATE******

Forgot to add that this motor has 32,000 miles

First I changed the plugs back to the stock copper ones, it was still pinging.

Changed out Cap, Rotor, and wires, all with stock A/C delco parts

The cap had some wear, but the rotor underneath had some burnt marks on it.

Took it for a spin and no pinging, yay, glad to have my 454 back

[Lukewarm256]

Spark plugs have a heat rating. Your new plugs could be holding too much heat in and causing premature detonation. Very bad. Could try different plugs, for sure.

Don't think the timing was moved? A hair too much advance can cause the pinging too.

Probably is the plugs however.

[Rickf1985]

TBI has a knock sensor mounted in the side of the engine, did you knock the wire off while doing the plugs? That would definitely give you the pinging since it would no longer let the computer control the timing. If it is till connected then go back to the last thing you did before the problem started which is the plugs and change them back.

[CJ7365]

Will check the knock sensor wire, first, then going to change the plugs back to what I had in there.