P0300 trouble code on a 2000 chevy cavalier


	Auto Repair Home	SEARCH POSTS	WHO'S ONLINE	LOG IN

Automotive Repair

Car Troubleshooting Topics
  Car Troubleshooting
  Engine Troubleshooting
  Engine Fault Codes
  Electrical and Wiring
  Transmission Problems

Car Repair Topics
  Car Making Noises
  Car Stereo Repair
  Heating or AC Issues
  Motorcycles and ATVs
  Tricks of the Trade
  Truck Repair Advice

Site Options:
  Login
  Sign up here!

Latest Forum Post

Drive Shaft Repair

I have a 2015 Chevy Traverse AWD. The fr...

2006 Toyoto Camry XLE Driver Side Electric Window Trouble

Hello, Looking for a little brain help ...

Tierod end change caused some kind of leak

Hello so I just took my car to the nearb...

2011 Dodge Nitro OBD scanner seems to drain battery in 10-20 minutes

When I bought this car in summer 2023, a...

Grounding Cable, 2017 Jeep Renegade Trailhawk

The Cable that connects my negative batt...

Rough Idle (Found new thing)

Hi everyone. First of all sorry for bad ...

equipment

hey yall. im a first year engineering st...

HELP

I have a 1956 1/2 ton panel truck, 69 35...

Howdy

    Just wanted to s...

ABS/Tractiob/Brake Lights on But No DTCs

Hello all, Recently while driving m...

P0300 trouble code on a 2000 chevy cavalier

Sign up here!

Email This Post

Auto Repair Home>> Automotive Repair>> Engine Troubleshooting

Davieray
New User

Dec 9, 2009, 3:19 PM

Post #1 of 3 (7294 views)

P0300 trouble code on a 2000 chevy cavalier	Sign In

I have a 2.4L twin cam. It runs extremely rough and then stalls. It has the p0300 code and a p0420 code. What should I check first to narrow down the problem?

Loren Champlain Sr
Veteran / Moderator
Loren Champlain Sr profile image

Dec 9, 2009, 5:31 PM

Post #2 of 3 (7290 views)

Re: P0300 trouble code on a 2000 chevy cavalier	Sign In

Davieray; P0300 is 'Random Cylinder Misfire'. Which means, the computer is seeing multiple cylinders misfiring for whatever reason. This could be caused by a lean or rich condition, or not. P0420 is 'Poor Catalyst Efficiency', which is more than likely a result of the P0300, and almost always requires replacing the catalytic converter. Converters, as we say, don't die. They are murdered. Meaning, that the misfires probably killed the catalytic converter and they must be addressed before addressing the cat. If you have a 'severe' loss of power, it is possible, that the cat is plugged, but we're getting a step or two ahead of the game, here. You may want to pull the spark plugs for examination and let us know what you see. Black and sooty, clean and white, ect... If you access to a vacuum guage, vacuum readings at idle and 2500 rpm would be nice, too.
Loren
SW Washington

Sidom
Veteran / Moderator
Sidom profile image

Dec 9, 2009, 9:48 PM

Post #3 of 3 (7287 views)

Re: P0300 trouble code on a 2000 chevy cavalier	Sign In

While you have the plugs out, take a good look at the coil housing (big white plastic piece bolted to the plug cover) those where good for carbon tracking and getting a lot of crossfire. Look for signs of black carbon tracks....... If it is bad and you change it, change the plug boots as well....

Email This Post

Search for (options) Privacy Sitemap