My catalytic convertor has been cut off of my 2006 Pontiac Grand Prix. And the check engine light was on when bought. I changed plugs and wires. When I accelerate the check engine light flashing off and on. When I slow down the flashing stops.
You will need to have the Engine Trouble Codes pulled. This is the only way to know why the check engine light is coming on and or flashing. Guessing is not a good idea when just about any local auto parts store will pull the codes for free. Post the codes below in the comments for more information.
If The Check Engine Light Flashing
The following may prevent more serious damage to your vehicle:
- Reducing vehicle speed
- Avoiding hard accelerations
- Avoiding steep uphill grades
- When you are towing a trailer, reduce the amount of cargo being hauled as soon as it is possible
If the engine light flashing stops and remains on steady, see “Check Engine Light Is On Steady” following.
If the light continues to flash, when it is safe to do so, stop the vehicle. Find a safe place to park your vehicle. Turn the key off, wait at least 10 seconds and restart the engine. If the light remains on steady, see “Check Engine Light Is On Steady” following. If the light is still flashing, follow the previous steps, and see your dealer for service as soon as possible.
Check Engine Light Is On Steady
You may be able to correct the emission system malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install the cap. The diagnostic system can determine if the fuel cap has been left off or improperly installed. A loose or missing fuel cap will allow fuel to evaporate into the atmosphere. A few driving trips with the cap properly installed should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition will usually be corrected when the electrical system dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. Poor fuel quality will cause your engine not to run as efficiently as designed. You may notice this as stalling after start-up, stalling when you put the vehicle into gear, misfiring, hesitation on acceleration, or stumbling on acceleration. (These conditions may go away once the engine is warmed up.) This will be detected by the system and cause the light to turn on.
If you experience one or more of these conditions, change the fuel brand you use. It will require at least one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off, your dealer can check the vehicle. Your dealer has the proper test equipment and diagnostic tools to fix any mechanical or electrical problems that may have developed.