Okay, that code is for cylinder 4 and says that the spark in the cylinder isn't lasting long enough. Common cause for that is a bad coil or the PCM coil driver is failing. A quick way to test the coil is to simply swap it with the coil on number 1 and see if you now get a code for cylinder 1. However if it is cracked I would replace it as it's likely from heat due to an internal short.
Swapping it would show if that was the case or if it's a different issue, say you swap it with 1 and the code stays on cylinder 4 and nothing changed, that would show it's the PCM or the wiring to it. Those coils all get power from the same source on the Brown wire with gray stripe. A quick test using a test light on each coils power feed would show if that was okay. Then use the test light in the place of the coil and see if the light flashes at all. If you have power but don't see it flash then it could be the driver transistor at fault.
Sunday, August 8th, 2021 AT 11:52 PM