Hi, so a month ago my car was having problems. It was shaking and the engine light was on. I figured it was an ignition coil and i changed the one not working after consulting with a mechanic. But the problem still didn’t fix. I then changed all the spark plugs and my car started working good. Now after a month i have the same problem, my car is shaking. Do i change all 4 of the ignition coils?
Probably worth doing especially if it’s a 4 cylinder (easier/cheaper) if it’s a coil and they’re easy to access then pull each one and look for and hairline cracks/splits on them and or oil to help pinpoint a specific one. Another thing to try is with the engine running spray a bit of water around each coil and see if there’s a change in engine noise.
Do you have a fault code for misfiring? Try swapping coils between that and another cylinder. If the misfiring follows a coil it’s a bad coil. If not check plugs, (compression), wiring to coils, and fuel system.
Use scan tool to see if it’s only one plug misfiring. Also pull the plugs to compare them to see if one’s different.
Change all the coils and plugs if you plan to keep the car….