"06" 4.0L intermittent p0300 and MERRY CHRISTMAS

[mumgow]

Just finished resolving issues with vacumn leaks last weekend and the next day it comes up with p0300. Having put in new Motorcraft plugs and wires recently but replaced the coil block with an aftermarket. I took it back and got another new one. Same make cause it had lifetime warranty. No problems. Took off this morning on vacation for the holidays. 400 mile trip. 50 miles in it skips a few times and the p0300 comes back. Runs fine for miles, code goes away. Then does it all over again. Checked when we get to our destination and codes gone again. Anyone have any insight? Also MERRY CHRISTMAS!!!

 

[08EddieCA]

Merry Christmas!!
Try moving the injector to cyl #1 see if it skips. Could be your injector going bad. Check the pulse with a noid light. I had a similar issue and it was the injector. I did the same exercise: intake manifold gaskets.

 

[BrooklynBay]

Check the new ignition cable & coil. The cable might have damage inside the rubber boot. Use a multimeter in the Ohm setting.