I have a 1988 Toyota Corolla EE80 that I bought recently, 1.3L carburetor engine with distributor ignition.
The engine idles normally at around 1500rpm idle when it's cold. But the moment the coolant approaches normal operating temperatures the engine starts to miss-fire and the idle speed stays around 1000~1100rpm.
I've checked and re-checked everything in the ignition system. took apart the distributor, checked all the cables and plugs.
The miss-fire gets more aggressive, to the point that the engine stalls it self if I have the vacuum advance on, even with the ignition fully retarded.
What can cause a miss-fire when hot? Valves? rich or lean condition?