wdgold

Well the misfire code on #4 cyl came back again so I swapped coil packs with another cylinder. After the code came back again is was still #4 cylinder so the coil is good, the next thing will be to change injector and see what happens. Could be a plug connection to coil or injector?

vintageman

Haven't re-read the whole thread but have been following it, have you swapped the #4 plug with another brand new one just to rule out a bad spark plug, that does happen, they can crack and cause a misfire. It does sound like an injector or either the injector plug or coil plug but, if you have not went down and bought a new plug to try it, that is one of the fasts things to do when troubleshooting this problem.
Good luck, keep us in the loop to try to help.
Tom

techrep

iTrader: (1)

Agree with Vintage...swap the plug and you can also swap injectors for troubleshooting..it could very well be the injector connector as well as the COP connector...you can read them both with a multimeter.

wdgold

I have already changed #4 plug out with a new one a while back but did nothing.

vintageman

Ok, time to give the plug connections and harness a good look, then if they are good, move on to swapping a couple injectors with each other. Keep it up, can't be much more.

Tom

wdgold

I swapped out with another injector so I we will see what happens today

vintageman

Good luck, hopefully the code will move, standing by for the results.

Rick's 06

I've been following along with this one too. Connector problems are pretty rare, so I'm betting you got it this time with the injector location swap. Keep us posted.

Edit:
As a side note, is there a rule of thumb for the life span of an injector, or do you just replace them as they go bad?

wdgold

To this date I have not seen an engine service light come in long enough to scan. One time the service light flashed briefly then went away.

bloodvette

2005, 5.4L. I had bucking at 1100 rpm in overdrive. It kicked a fault after about a week of this. Actually the check engine light came on and off a few times before I got my code reader. I bought an autotel AL419 code reader. Fault said multiple cylinder misfires. Went to the sensor monitor section and by selecting each cylinder individually and looking under the "last misfire counts" I observed a FEW missing cylinders. I eventually changed 4 coils with good quality ones (not from eBay)- about $75 each. In every cylinder the misfire counts went to zero. (I tried one then test drove, then another, etc.). I am 100% sure that my problem was coils failing because that's the only thing I did and it runs perfect and no misfires. Hope this helps. Good luck. John