89 cadillac brougham misfiring under load

[jimbo]

1989 Cadillac Brougham 5.0 4 barrel misfiring under load
need solutions

[dplotkin]

Plug wires, cracked plug insulator or fouled plug.

Dan

[Dave Shepherd]

As stated by Dan misfires in a carburated engine are pretty basic, assuming good compression.  If this is a 5.0 Chevy small block cam failures back then were common and did feel like a misfire, usually accompanied by some popping back thru the carb.

[TJ Hopland]

Its an Oldsmobile.  Its got a roller cam.  Very unlikely to be a cam issue. 

By far the most common issue I saw with those was the air heated choke not opening for various reasons.  This meant the engine ran rich all the time.  This eventually lead to a plugged cat converter.  This makes the engine idle pretty smooth but it just has no power.  It is also hard on spark plugs and eventually burnt rings and valves.