P1309 Misfire Monitor Disabled
Trouble code P0300 means:Random/multiple cylinder misfire detected
It means the coil or the spark plug is dead.
Trouble code P1399 means: Multiple / Random Misfire Detected Check gap of spark plugs or replace them
This is a Honda only code which means you have a random cylinder misfire. If you have not replaced the Spark Plugs & Wires, do so now. Use OEM spark plugs.
It means a cylinder 4 misfire. Check spark plugs, spark plus wires, possibly head gasket.
Misfire on cylinder #3, not sure of the cause (no spark, blown gasket, injector problem).
P0300 means random misfire detected which probably has to do with the spark plugs or the plug wires
P0303 is cylinder #3 misfire. P0300 would be random misfire. Either way you need to diagnose the case of a misfire. Check spark plugs, plug wires(if equipped), cylinder compression, fuel inectors, and wiring.
P0302 is a cylinder number two misfire. Causes include spark plugs, injector, internal engine failure, etc.
That error code is for a single cylinder misfire. Bad spark plugs or wires can cause this as well as a bad fuel injector.
Code P0304 on 2000 Ford Ranger is: Misfire at cylinder 4 detected. May be cause by a bad spark plug.