'99 3500 van Vortec
 

Engine runs ruff, and then has no power, and sets codes saying lean on both banks, parts store guy sold me a can of Cat converter cleaner, because they get clogged, I never heard of any cleaner to use in the fuel/toss in the tank, so anyone hear of this??

AND I reset the codes, engine fine for a few minits, the codes reset.....

anyone any clues???

:confused5:

Convertors can get clogged. Never heard of anything to clean them, just replacing them. Could it be injector problems?

Start with the basics - new plugs, gapped properly, and new coil packs, if so equipped. Replace them all at the same time.

Also check the mass airflow sensor.Any cylinder misfire codes?

Before you spend a cent on parts... if the converter is clogged there will be almost zero gasses at the tailpipe. Put a hand near the exit and have the Mrs rev the engine. If no blow... replace the cat.

I was thinking bad spider but that would be rich not lean

https://troubleshootmyvehicle.com/gm...uel-injector-1

If its a clogged converter you should be able to tell by the temp of the exhaust before and after the cat.