No check engine light but all cylinders misfire

DMCHONDAACCV6

MEMBER
2002 HONDA ACCORD
3.0L
V6
2WD
AUTOMATIC
162,705 MILES

Hi, I had some codes read prior to the purchase of this car. All cylinders showed a misfire, and a code for multiple misfire as well. The codes are P0300, P0301, P0302, P0303, P0304, P0305, and P0306. I also have a SRS light on as well and see it could be a number of things from researching. For the price of the car was a steal, but I want to make sure I am not over my head in price to fix it. The codes show it can be ignition coil, spark plug, EGR valve, fuel pressure regulator, or fuel injectors. Now the car idles fine, I highly doubt all fuel injectors are bad or the coils out at the same time. I have yet to do any digging in the engine yet, due to more focused on the title transfer and getting all that sorted out first. It has an aftermarket exhaust and intake on it just for further information. Is there a way to deactivate the check engine light or a possible blown fuse or light in the dash that may be the reason for no check engine light coming on? What would be the best route of checking things first and then so on? I will add pictures to the post for response answers-questions if that is possible after posting.

Thank you and ask away I am ready to get my hands dirty working on this issue.

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1 Reply

STEVE W.

MECHANIC
12,963 POSTS

Do the dash illumination lights come on to light up the gauges? If no then check fuse 9 in the under dash box. It powers the lights and the MIL light.

If the light does not come on during the bulb test and the fuse is good you will need to pull the cluster and check if the bulb was removed or taped over. Or put a good scan tool on it and see if the MIL light was requested on.

Then you can start doing diagnostics. I would ask if they added a chip or tuner to the car.

I would also check to see if the "aftermarket" intake meant they removed the PCV inlet tube. If it is drawing air from someplace other than through the airbox that could be an unmetered air source and act as a vacuum leak which would set misfire codes as it creates a lean mixture.