2000RPM miss/stumble/vibration?
 

I guys I'm hoping for a little direction here

I just replaced my well worn (200,000+ mile) 4.6 with a brand new, "old stock" 2004 4.6..the new engine was complete from oil pan to throttle body (even a belt and oil filter)

after the swap I have a significant miss/stumble/vibration right about 2000 RPM...I thought it might have been the Energy Suspension motor mounts, but it seems worse once the engine gets up to temperature so I'm thinking it's not a mechanical issue

a couple other things; the place that did the swap* didn't use the new engine's wiring harness and didn't use the new injectors...I have blocked off the hoses to the heated PCV because it wasn't plugged it, and that may have made a slight improvement (by that may be just in my mind)

any thoughts guys? maybe needs a tune? or the old style PCV set-up?


*I intended to do the swap myself, but the place I had planned to do the work disappeared and my chronic back issues picked a really back time to re-appear so I had to farm it out...the place is a Mustang shop and they seem to know what they are doing :-/ )

whats the condition of the crank damper?

it's brand new (came with the engine)

is it Auto or Man trans

manual trans with a new Ford nodular flywheel...

to muddy things further...it's worst when it's fully up to temperature and at part throttle acceleration from about 1500RPM to just past 2500RPM, and on deceleration from 1500 to just under 1000RPM

and it's much more noticeable in the first couple gears than in 5th

Check your transmission mounts. My car had a real vibration issue, especially when I put the car in OD. Turns out I had a broken tranmission mount.

cautiously optimistic...'cause when I'm wildly optimistic I usually end up getting kicked in the teeth ;)....but I think I got rid of that nasty miss/vibration/hesitation my car had...

I changed the plugs and that helped a lot, there were a couple pretty nasty looking ones but it still didn't fell 100%...

then I changed the oil, it was wildly overfilled (my 12 quart drain pan was FULL after the drain) and now it seems like it's running just right

I'm not so sure how it got so full (well obviously they put too much oil in, but I only provided them 6 quarts) and to be fair the dip sticks on our cars are crap, but at least now I know exactly where it should read when it's full

(but I'm still a bit bummed, I gave up on a 5.4 the day before the 5.4 intake saw the light of day :( )