[Nitro_Steve]

Hey guys, as the title says I have a 2009 Nitro 3.7L Coil-on-plug that i bought a couple weeks ago. When i bought it, it was running rough due to what I thought might be bad plugs, and was pulling a P0300 code and fuel system too rich code. I Changed the plugs as well as new coil packs, wires and injectors however, when I start it, the truck revs up and down, and it backfires every couple seconds. Could it be a vaccum leak? Any help would be appreciated.

 

[rickaren]

Dodge Nitro: Engine Problems / Code Errors

Dear Steve

That PO 300 code comes up alot for both the 3.7 & 4.0 Nitro Engine. The above Link might be helpfull. It could be a head gasket, valve or many other less expensive things. To help others please report back as to what you find. Also check out
Dodge Nitro ENGINE 3.7L - Service Information

that may be of help too. Good Luck!

 

[Nitro_Steve]

Thanks! Will do.

 

[rickaren]

• If the ignition system and fuel system checks out you may want to perform an engine compression test and leakdown test to see if there are any mechanical problems causing your misfire. Some common mechanical problems that cause misfire can be:
  • Broken valve spring
  • Broken piston ring
  • Worn valve guides
  • Burned valve
  • Timing chain or belt skipped tooth and engine is off time.

 

[Nitro_Steve]

Also, I forgot to mention that the truck had been sitting For several months before i purchased it. Could it possibly be bad gas?

 

[rickaren]

Chevron Techron Concentrate Plus Fuel System Cleaner - 20 oz.

I used this product to eliminate a PO 302 error code.

Chevron Techron fuel system cleaner is unbeatable in cleaning the entire fuel system and restoring lost power and performance caused by deposit build-up. - Cleans deposits from fuel injectors, carburetors, ports, valves and combustion chambers- works in one tankful while you drive to reduce deposit related engine knock, ping, run-on, and cold start problems- recommended for use every 3,000 miles- 20 oz. bottle.