What should I do when the check engine light is on and car is shaking when stopped?
Is your 4-wheeler rocking back and forth when stopped? It might be signs of an engine misfire.
It is a dangerous event and requires immediate attention. Here are some things you can do if you know your way around an engine.
Whether a big vehicle like a truck or a small Chevy, you can use this guide for all 4-wheelers:
Check the spark plug.
The first thing to do is to check the spark plug. Open up the engine and check which cylinder is misfiring. Disconnect the spark plug from that cylinder. Get a spark plug socket and use it to remove the spark plug entirely to take a closer look.
Once you examine the plug, you can tell the cause of the misfire. Here is what to look for:
- The fuel regulator has malfunctioned if your plug is soaked in oil or gasoline. It needs immediate professional attention.
- The wire that connects it to the ignition coil might be broken and needs replacing.
- The plug is covered in black soot. It means there was too much fuel, and the engine was running rich.
Test the coil pack
The ignition coil connected to the spark plug is responsible for powering up the vehicle. If this coil is faulty, it can cause a misfire.
Test it out by removing the wire from the spark plug and connecting it to an Ohmmeter instead. Check and compare your vehicle model’s resistance with the normal resistance range. If it doesn’t match, the coil needs replacing. It’s not the spark plug that has problems.
Compression failure
It could be that overall compression is not taking place properly. For this, you can run a simple compression test of the:
- fuel
- spark
- and air for each cylinder.
Remove the fuse of the fuel pump. Remove the spark plug and put a compression gauge there instead. Let the engine turn over a couple of times by starting the car. Write down the highest figure with each reading of every cylinder.
After testing each cylinder, compare the figures. All the cylinders should be in the same range. But if two are particularly low and are also right next to each other, you have found your problem!
It is where the head gasket needs replacing. Remove the cylinder head and replace the head gasket because it has gone bad and led to low compression levels.
If the cylinders have around about the same reading, the problem is not compression. Rather you should follow the next step below.
Call a professional mechanic.
Suppose you cannot find a faulty spark plug, bad coil pack, or compression issues. In that case, it is time to ask for a professional’s opinion. Don’t think there is anything wrong with the 4-wheeler, and keep driving! Rather call a mechanic before you get stranded with a breakdown.
