misfire and skipping when cold

[organic]

my truck has been acting up when cold for 3 weeks now, skips and bucks when i give it gas and all this goes competely away once it is warmed up.
I've been waiting for it to throw a code but i don't even have one pending.
anyone got any idea what it could be? if it was a sensor should'nt it show up as a code? i think this could be a real problem when the cold weather hits.


forgot to mention this is a 2000 ranger 4 liter

 

[alwaysFlOoReD]

Just guessing,
small vacuum leak...vacuum lines, loose bolts-intake system?
Can you do a compression and/or leak down test?

Richard

 

[organic]

thanks for the response floored,
I sprayed the crap out of the throttle body and vac lines with carb cleaner and that did the trick - along with getting the mouse nest out of the breather!!!!

 

[organic]

just a quick update - it started to skip again in a few days, went from only doing it cold to all the time, still no code appeared. i took it on an 80 mile round trip and it was skipping like heck and just as i got home a code popped up. misfire in cylinder 6.
i started with the cheapest fix first and put in a new sparkplug, lucky me - that was it!!
it had autolite plugs with only about 50 grand, i replaced with original motorcraft.