Dreaded P0300 on my 1997 Pathfinder

[Slumpert]

Well it has been a mostly uneventful 3 yrs for my daughter driving the pathfinder, but she called me and asked what to do since the check engine light came on. She verified the check engine light was not flashing so I instructed her to continue driving, keeping a close eye on everything as she was over 100 miles away at school.

When she got home for winter break, she told me the light went off on its own on the drive home. I hooked up code reader and P0300 was stored inside.

In looking up that misc code, and recognizing that I had already replaced all plugs, wires, cap, and rotor previously as well as fuel filter it was likely the distributor.

So I ordered a Cardone from RockAuto "A1 84-58600" for @105 shipped and it arrived the evening before she was set to leave.

What followed was my typical scenario of nothing was working right. I ended up determining the new part was not firing on cyclinder #3 (timing light would not flash on that wire), but not until I had already taken apart the old distributor to see was was going on as others had pointed that they wear out and indeed the inside of mine was nicely corroded in spots and the gear was not spinning smoothly.

I tried to reassemble it so she could drive back to school on the old unit, but the car was going crazy with misfire codes and flashing MIL when I installed it, so the Pathy was not going anywhere.

Rockauto was very quick in exchanging the part, I installed the new one today and the engine was still running really rough and the MIL was flashing and P0300 was the code but all wires were sparking with the timing light so I knew the distributor was not likely the issue this time.

I went about manually setting TDC, pulling #1 plug and using a long straw to double check TDC to the balancer, pulled the distributor again and checked all alignment marks. Still ran really rough and was "hard to time".

I pulled each wire one by one and #4 and #6 did not alter idle "much" when compared to when the other 4 plugs almost stalled the engine when pulled.

So I was thinking maybe some gunk had already gummed up one injector and was now working on the second and what was involved in getting access to them. Maybe needed to call actual dealership and pay for diagnostic.. Maybe needed to do lots of things, nothing was going to be easy or cheap.

I decided to test the plug wires themselves for resistance ( as it was the last thing I could think of, and as I pulled the plug at the cap for #6, I realized the wire was going to #4 plug...

Yes your VG33e engine will run with swapped #4 & #6 plug wires and I could not think of a more appropriate "misfire" code for such a stupid mistake.

Amazingly once I reset the plug wires all was well.....