So here's the story - 90 Blazer with stock 350/700R4/241. Chassis has 232k miles but who knows how many miles on the engine. Still has good compression and burns no oil to speak of. Problem was it would ping like crazy when I got on it, so I sarted down the list of things the factory manual says to check. I started by replacing the cap/rotor/wires/plugs and setting the timing - yes I disconnected the wire. It's at 0 degress in bypass mode and runs around 4 before connected. Still pings. Checked the EGR valve, which did need replacing as it was VERY sticky. Replaced the O2 sensor just because I already had a new one - stuck with the single wire since it's stock manifolds. Replaced the fuel filter. Better then it was, but still pings. Took a look at the fuel injectors with a timing light and find the pattern is a little puny and has a few drips. Buy a reman TBI setup since it was decent price but in the process of installing it I end up breaking off the clip that holds on the 700R4 TV cable. Oh well, I needed to change the tranny fluid anyway, right? Replace the TV cable and take it out for a drive. Notice three things right away. 1. Shifts are much crisper an at a little higher RPM then before. Guess the old cable needed replacing anyway. 2. I GOT RID OF MY STICKY THROTTLE!!! That has annoyed me for quite a while, but I'm not sure if it was the throttle body or the TV cable causing it. OH, Yeah 3. IT STILL PINGS So my mechanic checked the fuel pressure for me and it's fine 13.8psi. He suggested the harmonic balancer either may have spun or it may not be the right one. I'm going to run the engine up to TDC with a dial caliper this weekend to check and see if the timing mark matches. Beyond that does anybody have any suggestions? I'm about ready to pull all two of my remaining hairs out about this. The truck runs ok for a DD but any heavy wheeling or towing my boat makes it ping bad enough I'm afraid I'll tear it up. So all you experts break out the questions or suggestions. I'll be home all weekend and will check whatever folks think would be worth trying.