My 97 5.9L 360 Magnum dodge ram SLT gives the following codes. P0300, P0304, P0305.

I replaced the Catalatic Converter w/ a brand new one because it was plugged.

I replaced all spark plugs and gapped them correctly and replaced all plug wires and the distributor cap and the rotor.

I still throw the same codes P0300, P0304, P0305.(*after resseting the check engine codes*).

Any suggestions on what I should be looking for or what I should fix next.

Thanks,

Jeremy

 

I would bet your running rich. That's probably what killed your cat and what is 'wetting' your plugs and giving you the codes. Probably need to put it on a scanner to keep from blindly throwing parts at it. The fact that you get random and cylinder misfires means that it is probably not injectors, but you could have gotten bad gas that plugged more than one. I would give them a listen with a stethascope or piece of vacuum line. With a scanner, check map readings, o2 readings, trims, etc.

 

check for a vacuum leak

 

Hello,

I now also have the code P0307. Earlier this week I had found code P0303 but not since the replacement of the catalatic converter. Another thing is that if I put the petal to the floor I barely if even chirp the tires. I'm definatley missing power. Also the idle is to low and while in reverse it is so low that the truck dies. The idle in park after running the truck for awhile, is up and down idle between about 300 to 700 rpm's.
an
Thanks for all your help,

Jeremy

 

Vacuum leak would only help. 300-308 are misfire codes. 300 is random misfire. 301 is cylinder #1 misfire, 302 is cylinder#2 misfire, and so on. It could be many things generating the codes, but the fact that you just had to replace the cat would indicate that you have been experiencing a rich condition. If you had a vacuum leak, it would lean you out and you would nothave the idle/low rpm problem. If you don't want to buy a scanner or involve a shop that has one, I would first replace the o2 sensor with a NTK sensor. They are better than the stock Bosch sensors that are available at many auto parts stores and can be purchased for a fraction of the price (1/2.5) at Summit Racing (.com). If that does not work I would then replace the MAP sensor. If that doesn't do the trick, theIAT sensor could be bad.

You're squirting too much fuel and plugs don't fire when they're wet. Put it in second gear and run it up to 5.5k rpms at wot. I bet the thing'll run like a scalded dog.

 

...never rule anything out. I vacuum leak can cause the motor to run lean and cause a misfire in any cylinder, hence the random misfire code, and since it's missing and stumbling it will not idle fast. Anyways moving on, it could be your cam senser or your cranksenser causing your timing to go off.

 

Did you reset the PCM by un-hooking the battery for ~5 mins after replacing the cat and 02's?

 

what brand of plugs did you put in? when i replaced the plugs after my cat clogged i put in autolite's and it ran like crap. i changed them to the champions that are listed on the radiator support and everything is good. you might also want to check your plenum gasket. look down the throttle body and if you see oil pooled up then the gasket is gone.

 

I also corrected a low end stumble by swapping from Autolite 3923's to NGK of the proper heat range.

 

Hello Everyone,

The plugs I put in where Bosch Platinums w/ a single tip. I gapped the plugs to .035. I was wandering if the 02 sensor was bad or any other sensors where bad, wouldn't that throw a code. I checked the oil and it looks normal and is at the full level. Very clean. I checked around the engine for wet spots and no wet spots. However I felt the fuel injectors and 4 and 5 had almost no ticking going on at all or thier was a significant difference between them and the other injectors. What does that mean? I am going to replace the 02 sensor on Wednessday. Thanks for all your support, I am going to continue down your list in most significant order until this thing is running healthy.