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Hi Im David, sorry you are having these issues.....possible causes of these 4 codes areLow fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors. Rough running engine due to misfiring plugs. Many engines have misfire codes to indicate the cylinder effected, such as P0304 for number 4. A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture. A large air leak at or near the number one oxygen sensor would also cause a lean mixture. A plugged converter will cause of host of driveability problems as well as set this code. A severely plugged converter will result in the inability to increase rpm when under load. Look for a code such as P0420 -- catalytic converter efficiency below threshold if the converter indicating a faulty converter. A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area. The Mass Airflow sensor will also cause this problem. It would be accompanied by a code such as P0100 -- Mass Airflow circuit malfunction. The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture. Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
are you mechanically inclined with vehicles at all?