crappy idle

[Pete M]

so the engine lopes and struggles to maintain a proper idle.  if I pull the spark plugs off of #s 4 or 5, there's no change in sound or rpm.  but there's definitely a spark, I can feel a click from the fuel injector, and the injectors ohm out at 14ish.  the injectors are new 4-holes.  can they be bad even though they indicate to be good?  I guess after dinner I'll start the process of pulling the rail and swapping in 2 of the old injectors just to see if there's a change.    or maybe tomorrow if the mosquitos are bad. 

[Eagle_SX4]

I don't have any experience with failing spark plugs. However they are easier to check than pulling the fuel rail the change injectors. Maybe start there.

[pizzaman09]

I've had a spark plug ceramics crack on me and missfire.  I've also had boots burn through and arc to the block.  Might as well check the distributor cap and rotor.

[Pete M]

finally got to fire up the engine and the idle and rev is VASTLY improved after swapping out 2 of the new injectors for old ones.  pulling the spark wire from those 2 cylinders before didn't change the idle before, so I figured those were the bad injectors.

[Pete M]

brought home, cleaned up and installed 6 ford branded, fat body, orange top injectors from an Expedition and the idle is spot on perfect.  

[fiatslug87]

You got a picture of those injectors?

[Pete M]

the factory ones in the junkyard will say Ford on them.  I'll post some long term updates whenever I finally get to drive the truck.  right now it idles and revs fine, but there's no load on the engine.  it's still going to be a while before that happens, but at least this hurdle is behind me. 

 

 

 

[pizzaman09]

Very nice.  Sometimes one just doesn't get lucky with new parts.