91' Camaro 305
Starts up, but after running for a little while, engine cuts out and sometimes smokes out of throttle body when it cuts out. Sometimes it will start right up and run fine for a little while, other times it will refuse to start and that's when the smoking usually occurs. Problem may occur when the heater is turned on, but I am unsure if this is coincidence or not. Any input would be greatly appreciated. No one can seem to figure out the problem. No codes shown. Put on new cap, rotor, plugs and wires already. Do you think it could be the distributor? Thanks

I am not sure but I think the only thing the engine and heater controls have in common is vacuum. Try plugging the vacuum line to the heater and see what happens. Also, I know this will sound stupid but check the alternator output. My brother-in-law had a Chevy pickup and the alternator went bad and caused all kinds of strange things to happen.

Checked vacuum, it was ok. Alternator output was good, Ill try a new distributor. Thanks , Ron

What is the timing set at? Another thing to check is the EGR valve and see if it is working under vacuum. Check for any vacuum leaks on the manifold.

Get one of those oil squirt cans and fill it half full of gas. The next time it won't start, squirt 4 or 5 pumps of gas in the throttle body and see what happens. If it runs then you have narrowed it down to the fuel system...filter, pump, solenoid if it has one, etc. If it doesn't change anything, at least we can eliminate that part.

sounds like a plugged cat you might check for a good exhaust output at the pipe.
my 81 Z did the same thing and it turned out to be the cat.