Here's my friend's problem we're trying to figure out. I know nothing about K20a3's. Car is an 02 Civic Si / EP3 ALL STOCK minus a catback that doesnt' matter.

The only thing he did was put gas in it, drove it home and it started sputtering/misfiring. It threw cylinder misfire codes in all cylinders.

We've changed out the gas to new gas... and it's like it's running super rich. If you pull out an injector plug or two while it's wanting to start, it'll start and run like it's fine for a few seconds. We tried tracing it to the fuel pump assembly, pulled the power to the fuel pump after a few cranks, start the car, and its fine, it runs for those 3 seconds smoothely/like it should. We swapped fuel pump assemblies thinking it was the internal fuel pressure regulator in the pump assembly and it didn't do anything.

ANY help/input would be appreciated. I don't see why any valves would be bent unless valve float is very common on these engines or anything. He did do one pull in first gear on his way home, but that shouldn't have done nothing unless he mis-shifted which he did not or downshifted into the wrong gears or anything.

I truely believe it is fuel related. Is the fuel dampener on the fuel rail a common problem? How about the fuel pump assembly? (we've swapped out with one from the junkyard)

Also, is there some stupid sensor or something that could've came loose?

ANYYYY Input?

Thanks in advance.

 

defanitly check your main ground, and it could also be a coil problem

 

GET your PID's on the scan tool see whats working corectly find specs and see which sensor is in line and which ones arent. Diagg is a bisshhh lol

 

agreed^