The check engine light indicates that you need to service a vehicle soon. If your Nissan Altima has a flashing check engine light means that there is a catalyst damaging misfire (it can damage the catalytic converter and O2 sensors).
There will always be trouble codes associated with the Nissan Altima’s check engine light flashing. The first thing you want to do is look them up with an OBD II scanner.
A code scanner is cheap. Use it to discover exactly why your car’s computer flashed this light. Also, most parts stores will scan your vehicle for free if your check engine light is on.
A misfire is the number one reason your Altima’s check engine light will flash.
Your car’s ignition system consists of spark plugs, plug wires, and ignition coil packs (older vehicles have a distributor that has the same function as coil packs). These parts work in concert to ignite the fuel in the combustion chamber at just the right time.
P0300 indicates that your Altima’s engine is misfiring, but it can’t detect which cylinder it’s coming from. This code is often thrown when there is a fuel issue, a timing issue, and not just bad ignition components (most likely).
If the only code your car has is for a cylinder-specific misfire. Start with pulling the plug and taking a look at it.
These trouble codes correspond with a specific cylinder misfiring (cylinder number corresponds with its place in the firing order). For example, P0301 indicates the Nissan Altima is misfiring in cylinder 1.
Although it’s a bad sign when the service engine soon light flashes, when one of these codes comes up with it (and nothing else), it’s almost always one spark plug or ignition coil. A leaking fuel injector can also cause a cylinder-specific misfire code.
There are other misfire-related codes as well, but those are the most common ones.
Keeping in mind that any engine needs air, fuel, and spark for ignition, your Nissan Altima’s fuel system can often cause the engine to misfire. It can run too lean or rich. Alternatively, there could be too much.
While a majority of the time, the flashing check engine light is going to be caused by a misfire related to your Altima’s ignition system or fuel system (as stated above), other issues can cause it.
Do not drive your Nissan Altima with a flashing check engine light.
When your engine is misfiring, it dumps raw fuel into the exhaust. This raw fuel can detonate, which causes damage to the catalytic converter and the exhaust system itself.
A flashing check engine light means you should not drive your Nissan Altima until you’ve fixed the engine.
If your Altima is shaking and the check engine light is flashing, it’s likely one or more of your car’s cylinders is misfiring.
We recommend that you don’t drive, if at all possible, until you diagnose and fix your Altima’s flashing check engine light.
Just pretend that it’s letting you know that it will cost you way more money to fix the problem if you keep driving it.
If your car has a flashing check engine light, it means you need to service the engine now. So don’t drive your car.