CEL on, then off, then on, then off....P0304&P0343

[david m]

1234567890

[LMP]

MIsfire is common..specially with #4 due to oil invasion for failure of cover gasket....but this is new as you say....faulty coil (it sits on top of #4 spark plug) /spark plug is a possibility , of course.

No personal experience with cam sensor failure..but check for wiring, plugs..Here is what KIA says:

2001 > G 2.0 DOHC > Engine > Engine Control > P0343 Camshaft Position Sensor Circuit high input
The Camshaft Position Sensor (CMPS) is a sensor that detects the compression TDC of the NO. 1 cylinder. The CMPS consists of a hall type sensor and a target on the end of the intake camshaft. When the target triggers the sensor, the sensor voltage is 5V. If not, the sensor voltage is 0V. These CMPS signal is sent to the ECM and the ECM uses the CMPS signal for synchronizing the firing of sequential fuel injectors.
If there is no signal, the ECM judged as a fault and DTC is set.

DTC Detecting Condition
DTC Strategy Rationality
Enable Conditions Engine speed > 600 rpm
Threshold value No signal for crankshaft revolution of : > 200
Diagnostic Time Continuous
MIL on condition After 2nd driving cycles

However, if the codes are freak and do not impair driving , do not go for a cure that is worse than the problem....