recently my 99 explorer shows codes p0175 and p0304. I know is a misfiring and system too rich on bank 2. I have change my plugs and have my spark wires check. Other than that i also throw a bottle of fuel injector cleaner in my gas( maybe helpful). The CEL lights still lights on, what should i do? Thanks!

 

P0340 is the (CMP) Camshaft Position Sensor/Circuit malfunction.. P0340 DTC should be addressed before trying a diagnosis for P0175..

 

but i though i said p0304?

 

Yes you did..sorry.. get'n late, and a long week..

How many miles on the clock? Which engine? 4.0/5.0.. Does the engine have a steady misfire? or on an accell.. If the plugs are new, and the wires are new/good, no base engine issues, then the next thing to check would be coil output/s and then fuel metering. The light flash or steady on? And you changed out the plugs/wires and then canceled the light and it returned?

 

it runs on a 4.0 sohc engine. When i change my plugs, i did disconnect my batteries and the light returned after a week drive. The light is steady on all the while. Shall i check on other things?

 

Are you actually able to detect/feel the misfire? Whats the mileage on the X..

Since you changed plugs, and if your 'sure' the wires test/prove out, (not greater than 7K ohms per foot) and not breaking down , then the coil pack may be an issue, and can/will set a misfire code if failing.. The P0175 would be a secondary concern at this point.. The misfire code should be addressed first..

The MIL will blink once per second when a misfire is detected severe enough to cause catalyst/converter damage, and if the MIL is on steady due to a misfire, it will indicate the limits for emissions was exceeded and cause the vehicle to fail an inspection/test.

I'd probably be looking towards the coil pack for the misfire.. Ignition components seem to fail at a higher rate.. Possible injector/circuit, but a guess without test/scan data..

 

the car has 136,000 miles on it right now. I can't really feel the misfire but when i start my car or even accel on it, there is a grinding sound in it. But it will be just when the engine is cold. Some people told me that my cam tensioner might be the cause.