2000 Chevy Camaro RANDOM MISSFIRE CODE P0300

MRLOPEZ

MEMBER
2000 CHEVROLET CAMARO
V8
2WD
AUTOMATIC
71,000 MILES

I BEEN WORKING ON THIS VEHICLE FOR THE PAST THREE DAYS.I HOOKUP MY SCANNER, GO UNDER MISSFIRE DATA. SOON I START VEHICLE CYL.#6MISSFIRE ONLY AS VEHICLE WARMSUP AND IDLES DOWM TO SPECS. CYL.#2 STARTS THEN 4, 3, 1 #6 STOPS SOMETIMES 5 AND 6 BUT #2MISSFIRE ALOT.I REPLACED WIRES AND PLUGS. CHECK FOR LEKS WITH PROPANE AND WATER. CHECK COMPRESSION AND FUEL PRESSURE.I ALSO SWAP COILS AND INJECTORS TO SEE IF OTHER CYLINDERS WILL MISSFIRE LIKE #2 BUT THE PROBLEM REMINS THE SAME ON #2 ALL CYLINDERS MISSFIRE BUT #2 MISSFIRE ALOT. THIS VEHICLE HAD AN AFTERMARKET ALARM AND I REMOVED IT.I ALSO REPLACED IGNITION MODULE, REMOVED MAF AIRFLOW AND SWAP. IDON'T KNOW WHAT ELSE TO DO. THANK U

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

A code P0300 may mean that one or more of the following has happened:

Faulty spark plugs or wires
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector(s)
Burned exhaust valve
Faulty catalytic converter(s)
Stuck/blocked EGR valve / passages
Faulty camshaft position sensor
Defective computer
Possible SolutionsIf there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.

If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.E. Spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.K.A. Coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.