93 Blazer 4.3 Not running right

93 Blazer
4.3 vortec

I was having a problem with it dying when it got warm. I have replaced the Dist Cap, Rotor, Plug wires, Coil, Pickup coil and Ignition module.

Now it will start and run good at idle but has NO power when driven!

I drove it about 3 miles it ran fine for about half way then it lost all power and when I got back the manifolds were cherry red which fire/melted the rubber on the plug wires and it was also glowing under the truck around the muffler/converter. Back passenger floorboard was hot, but that is above the muffler? I just put a new muffler and tailpipe on it a month ago.

It is throwing a 43 code Spark Ignition failure code.

And I am Stumped
There is a good amout of air moving through the tailpipe so could it be the Catalytic Converter clogged?

Any help would be apreciated
Thanks

Have you set base timing by disconnecting the bypass wire?

What is engine vacuum reading at idle and at 2K rpm?

93 Blazer
4.3 vortec

I drove it about 3 miles it ran fine for about half way then it lost all power and when I got back the manifolds were cherry red which fire/melted the rubber on the plug wires and it was also glowing under the truck around the muffler/converter. Back passenger floorboard was hot, but that is above the muffler? I just put a new muffler and tailpipe on it a month ago.

It is throwing a 43 code Spark Ignition failure code.

And I am Stumped
There is a good amout of air moving through the tailpipe so could it be the Catalytic Converter clogged?

Any help would be apreciated
Thanks

Here is the basic explaination of Code 43;

"Code 43 indicates that there may be a malfunction in the Electronic Spark Control (ESC) circuit.
ESC is used to sense spark knock (pinging) and retard the timing to eliminate it. A knock sensor (located at the rear of the engine block) sends signals to an ESC module which then signals the ECM that knocking is being detected. The ECM will retard the timing by as much as 20 degrees in 1 degree increments. A loss of knock sensor signal or loss of ground at the ESC module will cause the signal at the ECM to remain high. The ECM will act as if no knock is present, and may possibly result in engine damage, if there is detonation.
Loss of the ESC signal to the ECM will cause the ECM to constantly retard the timing to its maximum. This results in sluggish performance and a Code 43.

The conditions for setting this code are:

Engine is running
ESC input signal has been low more than 2.23 seconds

Typical causes for this code include:
1) Open or shorted knock sensor
2) Loose knock sensor
3) Excessive mechanical noise within engine
4) Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM
5) Intermittent open in the EST line to the ignition module"


(source: courtsey of my old GM trouble shooting manual)

Hope this get you looking in the right direction.