Engine Performance problem
1998 Honda Civic 4 cyl Front Wheel Drive Manual 140000 miles
Hi I have a 1998 Honda civic dx that has been driving me nuts. When I start the car it will run really rough for about 30 seconds, the idle will almost drop off and pick back up. When I apply the gas it hesitates and will clear up after a few seconds. Also when I first take off engine cold the car will fall on its face, so I have to feather the throttle and soon after the car runs fine.
The check engine light is on and has a code of P301, says misfire in bank 1.
I replaced the spark plugs, wires, cap, rotor and fuel filter, this did not help. Also I checked the fuel injectors with a multimeter ohms reading and they all check out equal. Please help.
Engine running rough or misfiring can be cause by the following-inspect and test all the following below: 1. Defective spark plug.
2. Inadequate spark/coil, defective spark plug wire.
3. Lack of compression
4. False air leakage.
5. Faulty fuel injectors.
6. Insufficient fuel pressure.
7. Contaminated fuel.
8. EGR valve that is leaking.
9. Oxygen sensors.
10. Throttle position sensor.
11. Idle air control valve.