hey yall, sorry for being post crazy lately but i just got tags on my truck yesterday and have been running into some issues. most imporantly (besides my tail lights not working) is MISSFIRING UNDER LOAD

i have set, and reset my timing today trying every possible setting to try and shake these missfire blues to no avail! it start at low rmp and seems to get better the higher you go. yesterday when i first started driving her it didnt missfire at all but as the day went on she started missfiring until finally i had to limp home....

i have straight pipes (no cats, or mufflers, 2.5" tube, racing X pipe, BBK shorttys) so i hear pretty much everything thats going on and these arent ittle pings massive predetonation. its causing excessive temps in my engine and its really stressing me out...i missed a GREAT job opporunity because of this today

 

just checked plug wires, and i seriously doubt its crossfire (new plugs, wires, coil, cap, rotor)

 

Checked timing yet?nevermind. I blinked while reading. I had to replace the hot wire on my coil several years back. It was cooked pretty bad and the sheething was coming off of it causing issues. Are your coil power wires discolored at all or frail looking?

 

missfiring under load is usually cap and rotor

 

brand new MSD cap,MSD rotor,MSD coils, plugs(motocraft), and MSD wires installed less then 100 miles ago

 

ill check them but Im not sure, and the little can (i heard it blocked out radio interference) separated from the wire connecting it to the harness.



Oh yeah.... it missfires unles slight load, but if it kicks down to accelerate it dont doesn't missfire. i just replaced the MAP sensor too, now it idles better and doesn't spit raw fuel out of the tailpipes. but still missfires.
today it was blowing smoke and spewing oil out of the valve covers but i found my PCV breather was full and was not able to flow fumes so i removed it and replaced my PCV. the smoke cleared up mostly too.


could i have fouled my plugs out this way? could i have been getting so much crank case pressure it pushed oil into my intake?


i pulled the #5 plug out (first towrds radiator on drivers side) and it was clean, but was slightly discolored.


also another idea i had was to pull all my plugs out and replace them again since they are gapped to .55 (6 liter mod)

 

check them all....

Have the ignition module tested too.. and make sure ALL the grounds are clean... on these trucks any dirty grounds and the Ignition system suffers greatly

 

Double check your plug wire order. And with the 6 liter mod I assume you advanced the timing. Did you try stepping back down to 10*?

 

yep i sure did, with no change.

 

im doing a "big 3" upgrade today hopefully!