truck shakes bad on cold start up
 

lately my truck shakes/vibrates really violently upon cold start ups. itll do this until you pull out on to a road and are going over 10mph.
its a 94, auto, 4x4, 5.0l
any ideas??

Plug wires, distributor cap are possibilities. Definitely sounds like a misfire.

i just replaced the cap and all plugs about 8 months ago. but can it be a misfire when the truck is completely fine the second you go over 10 mph? and also totally fine if the truck is still warm when being started?

How long have the plug wires been on that engine? Sounds like you may have condensation grounding out or causing crossfire in the plug wires until the wires heat up and evaporate the condensation. If the local weather has been especially humid or you have had rain recently, I would look at replacing the plug wires.

ive never replaced them and ive had it for almost 2 years. i live in MI so its far from humid lol but we've been getting frost and TONS of condensation every morning...could be the problem. thanks for the info

Pull the wires and clean the terminals on both the distributor and cap ends then use some dielectric grease to seal the boots to the posts on the cap and where the boots seal around the plugs.

My 5.0 in the Bronco did the same thing. It took a new set of injectors to make it run and start right. You might see about used sonic cleaned injectors if you just wanna save some bucks. I bought new and spent nearly a grand.

You never finished this thread:
https://www.f150online.com/forums/pr...ine-light.html
Did you ever pull the codes??? What were they?

This one either - what did you find?
https://www.f150online.com/forums/pr...loorboard.html

What do the plugs look like now? What gap did you set them to? Did you route the wires exactly as shown here?

https://www.supermotors.net/getfile/...ute94up_5l.jpg . https://www.supermotors.net/getfile/...rkplugdiag.jpg

What's the fuel pressure? Is there any chance it's contaminated? Try some fuel drier (HEET).

the engine light never came on again after i flushed the radiator and refilled.
the clunking...my rear dif went out and it stopped after that was replaced.
what do you mean what do they look like? i dont remember the gap but it was whatever the people at the auto store told me to do. havent checked fuel pressure. im going to run a bottle of fuel system cleaner through it and see if that helps

"What do they look like?" means take at least a couple out & look at them. Then compare them to the diagram in that post that you quoted.