2002 Durango 5.9L

I failed my smogtest today. because of Code P0300...I just replaced my spark plugs . wire and distributer cap and rotor..previously I was getting codes P0300 P0301 and P0305 and now just the P0300

The guy at the test facility suggested that because of the multiple misfire..he thinks it is the crankshaft position sensor...or camshaft position sensor...
Should i replace these and does the 5.9L even have a camshaft position sensor? Also, if i buy the part from Autozone or Napa is it just as good as Mopar? I'm just trying to save some money.

 

what type of plugs did you put in the truck? if you put anything other than champion copper core plugs in there you need to change it, the cap and rotor should have brass contacts in them, and the wires should be mopar or msd 8mm or better

the next thing i would look at is dirty fuel injectors run a bottle of injector cleaner through the truck and see if that helps, also check the plenum (open the throttle body and shine a flashlight down there if there is oil in the bottom you need a new plenum gasket) im sure hydra will have more ideas on top of what i have already said

 

I put autolite copper core plugs. Are the brass contacts and 8mm wires totally necessary?

 

the wires and brass contacts provide for better contact and better transfer of the spark(well, actually the electrical pulse which creates the spark), if it works fine w/o them its fine, but if you are still having trouble i would say yes they are pretty necessary as a troubleshooting step, take out as many variables as possible and give you the best chance of getting a good strong spark., the autolite coppers should be fine, its what i had in my truck for a while and they ran fine for about as long as i expect copper plugs to last.

 

Not sure if you should replace the sensors, however you do have a Crankshaft sensor on the rear of the motor (i think passenger side). The Camshaft sensor is also called a Pick Up sensor, it is located under the distributor cap.


You do not NEED a brass contact cap and rotor, they are just better.

Get some dealership Mopar wires, Mopar Performance wires, or MSD 8.5mm Red wires. These work great and they are all I would buy period for a Dodge.

Plugs should be the cheap Champion Copper plugs and they need to be gaped at .040

The main thing you have to think about is, "you are having issues", replace the parts with parts that are KNOWN to work, not parts that a shop/parts store tells you will work. Trust me!

Take back the parts that you have that are not what I specified and tell them they don't work, get your money back and get the correct parts.

NAPA and Auto Zone have good parts.

02 sensors you should get from a dealer.

 

Update... Turns out my battery was almost dead..I guess causing my multiple misfires and a plug was not tapped properly in cyl5. Now I worry that my bad battery was messing up my alternator. The autozone guy said it would probably go soon and was measuring 13.88...what does this mean? Well at least I passed the smog!

 

13.88 is fine if you are really concerned take it to a repair shop that specialises in battery and electrical work. They can also check the amps that the alternator is supplying.
Approximately 14 volts is what the alt. needs to supply to the battery.

 

Technically any thing over 12.8 is charging, however with my experience the normal output is 14.4 - 14.6 volts. I would think about replacing it with a brand new one, not a re-build.


13.88 is not a good sign, also what was the Amp output?