This past Monday on my way to work, my car started bucking and the check engine light started flashing. I checked the code, it was P0301, Cylinder 1 misfire. Since then I have…
First I Changed the Ignition Coil Cylinder 1
Then I Changed the Spark Plug Cylinder 1
Changed the Fuel Injector Cylinder 1
Performed a Compression test Cylinder 1. Passed 185 psi
Visually inspected the wire harness
Visually inspected the vacuum hoses
Swapped the ECU
About 2 months, ago I installed a new fuel pump, fuel filter and pressure regulator.
When I first start the car, it runs fine. While it is still in park, I can rev ’til the cows come home without issue. When I put the car in gear and drive for a few seconds, I get the Flashing CEL and Misfire code(p0301 only) comes back every time. Also, I can feel the car missing, so I know its not an erroneous code. What should I try next?
I would recommend checking for intake manifold gasket leaks. It is a common failure that may cause a misfire problem. I have provided a diagnostic chart to help assist you.
Code P0301 Diagnostic Chart