1987 Elky 305 Engine

[elky1987]

A new thread to a problem posted in 2005,

Engine starts and runs smoth. After a few minutes the idle gets a little rough. After 10 minutes the motor really runs rough when accerelating. When pressing further the motor seems to be missing. The sound is like (ka-chunk)(ka-chunk). You have to feather the petal to smooth out. Engine does not stop . Recent new plugs, plug wires and dist. cap

Previous suggestion is possibly bad catalytic converter and some sensors. Appeciate some imput.
Thanks

[silicon212]

Have you looked at the carb? To me, this is where the issue likely lays. I'd suggest possible cam lobe failure, but that engine being an '87 should have roller lifters in it.

[PeteA216]

Silicon, you're all over these forums aren't you.
I had a similar problem with my Caprice a couple of years back. To be honest with you I never figured out the cause of the problem. I put a colder thermostat in (from 195 to 170) and running the engine cooler fixed the problem.

I'd suggest possible cam lobe failure, but that engine being an '87 should have roller lifters in it.

How would a worn cam cause that (curiosity)? I did find out after tearing it down that my 305 did have a severly worn cam more so in some lobes than others. Would that have been the cause of it's running horrible when warmed up?