Aleromod.com - View Single Post - Engine code P030X, can't get past 2500 rpm

knowledge8069 · 11-11-2009, 06:10 PM

Quick background of my ride:

2000 GS Coupe
Automatic Transmission
2.4L LD9
GM Supercharger Kit
109,000 miles
Amsoil 25,000 mile drain synthetic oil since 16,000 miles on car

Parts serviced: both front wheel bearing sets, both window regulators, brakes, calipers, tires (normal stuff), no drive train issues yet

My car threw a code last night after a 40 mile drive. Everything was fine until I got to a stop sign, idling, and noticed the car was jerking back and forth. "trac off" light came on. Brought it to Autozone the same night, they read OBD-II code P0301, which is "cylinder 1 misfire."

Bought new spark plugs (Rapidfire #8 which is current AC Delco equivalent for plugs that come with s/c kit) and new plug boots. Gapped the plugs at .050 as GM s/c kit instructions state. Installed parts and the jerking stopped. Thought it was fixed, started the test drive.. Got to about 4000 rpm before the car bogged down. I was unable to get it past 4000 and after getting there it got worse to where I couldn't get above 2500. Will only do about 30 mph. Limped it home, went out this morning and bought an ignition coil housing. Installed that, no effect. Tried putting some clean gas into the tank, thinking it was bad gas. That did nothing. Now the indicator lights are "service engine soon" and "trac off" which goes on and off at will. The "service engine soon" light will sometimes flash, other times not.

Looking at the code description, these are possible problems:

A code P030X 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

There has been a rattle for a few months coming from the catalytic converter. Sounds like a piece loose inside when I put my ear up to it. Since it's fairly expensive ($350) to get the preassembled exhaust system I've put it off.

Do you all have any ideas? I'm broke right now after 7 years of school, so I have limited means. Trying not to buy unnecessary parts if possible. It seems to me that the engine is being choked out at higher rpm.. It's smooth as normal up to around 3000 rpm, then it chokes and gets worse. Any help you can offer would be greatly appeciated. Thanks in advance.

11-11-2009, 06:10 PM	#1
knowledge8069 GX Member Join Date: Dec 2003 Location: Minnesota Posts: 48	Engine code P030X, can't get past 2500 rpm Quick background of my ride: 2000 GS Coupe Automatic Transmission 2.4L LD9 GM Supercharger Kit 109,000 miles Amsoil 25,000 mile drain synthetic oil since 16,000 miles on car Parts serviced: both front wheel bearing sets, both window regulators, brakes, calipers, tires (normal stuff), no drive train issues yet My car threw a code last night after a 40 mile drive. Everything was fine until I got to a stop sign, idling, and noticed the car was jerking back and forth. "trac off" light came on. Brought it to Autozone the same night, they read OBD-II code P0301, which is "cylinder 1 misfire." Bought new spark plugs (Rapidfire #8 which is current AC Delco equivalent for plugs that come with s/c kit) and new plug boots. Gapped the plugs at .050 as GM s/c kit instructions state. Installed parts and the jerking stopped. Thought it was fixed, started the test drive.. Got to about 4000 rpm before the car bogged down. I was unable to get it past 4000 and after getting there it got worse to where I couldn't get above 2500. Will only do about 30 mph. Limped it home, went out this morning and bought an ignition coil housing. Installed that, no effect. Tried putting some clean gas into the tank, thinking it was bad gas. That did nothing. Now the indicator lights are "service engine soon" and "trac off" which goes on and off at will. The "service engine soon" light will sometimes flash, other times not. Looking at the code description, these are possible problems: A code P030X 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 There has been a rattle for a few months coming from the catalytic converter. Sounds like a piece loose inside when I put my ear up to it. Since it's fairly expensive ($350) to get the preassembled exhaust system I've put it off. Do you all have any ideas? I'm broke right now after 7 years of school, so I have limited means. Trying not to buy unnecessary parts if possible. It seems to me that the engine is being choked out at higher rpm.. It's smooth as normal up to around 3000 rpm, then it chokes and gets worse. Any help you can offer would be greatly appeciated. Thanks in advance. Last edited by knowledge8069 : 11-11-2009 at 06:13 PM.