P0301 when starting

[Passerat]

Hi everyone,
i have, sometimes a problem when i try to start my jeep, it starts on only 3 cylinders and the code P0301 appears.
It happens only when the jeep is cold during staring, never while the jeep is running.
If something have any ideas it would be very nice.
Thanks a lot

 

[TexasTJ2004]

Is it 4 cylinder or 6?

 

[Passerat]

Its a 4 cylinder 2.4l
And i don't have this problem at every start, sometimes i have it ..

 

[RMETeeJay]

It's a cylinder 1 misfire. What are the age and condition of the ignition components on that cylinder? What does a test light on the cylinder's injector show?

It can actually be caused by many other components. Here's a page with a full list of the items to inspect:
https://www.obd-codes.com/p0301

 

[Passerat]

Ignition cables and spark plugs are recent and i still have the problem sometimes, i heard about a valve in the fuel pump that might me in cause

 

[TexasTJ2004]

I have seen it happening when I was running with power removed from the injector.
The fuel pump create the pressure for the entire rail, and the injectors are fed from the rail. With faulty fuel pump, you would be seeing issues on different cylinders as well. Can you swap the injector between different cylinders?
Also, check the power to the injector.

Also, I am assuming that the cylinder is in the good shape, and there is nothing wrong with it. You can measure the compression in it, to eliminate this.