2009 (shaky start) after being driven

hello,

i was injured and my truck sat at an incline with the hand brake set for around 6 months driven around every 3 weeks or so. i also got a new engine put in because of a different problem.

when i start the engine with no heat, (overnight) it starts smooth and gets into reverse very smoothy.

after it has been driven and has warmed up, if i get out for a while and then get back in and start it, the truck shakes pretty darn hard. harder than I've felt. all other mechanics agree its unusual.

the person that put the new engine in is a master mechanic I've known for 30 years and we grew up together, we have spent hours together trying to figure this out checking motor mounts, and other mounts - ha was under the truck moving around everywhere. he has shown me the computer when attached to my vehicle that everything checks out, air, idle, rpm, we checked every menu together and everything is in the green. he took one of the sensors off the top front of the engine and cranked the engine, it didn't start he was just checking that all cylinders were firing. he said there is another sensor behind the air conditioner bracket that he cant get to without taking off a lot of stuff.

also, when i take it out of park and put it into reverse and let go of the brake there is a little hesitation to start reversing; like another brake is letting loose to let me start backing up. there is no hesitation while putting it into reverse, though.

the short is - when i start it cold everything is smooth, but when my truck has been running a while and i shut it off, next time i start it, it shakes pretty hard from the engine bay and possibly a little further back i cant tell. and when i put it into gear there is a small hesitation when i start to move as if a "brake" is on for a split second and everything runs fine after that.

 

The shaking only after being started up sounds a lot like a problem I had on a first gen with a leaking fuel injector.

If it's set overnight it would leak enough fuel into the cylinder and it would then evaporate after the fuel rail lost pressure, but if it only sat for a few hours the fuel rail pressure would dump out of that leaking injector and still be sitting in the cylinder the extra fuel in the cylinder would cause a misfire or detonation and lead to the shaking in the engine, the engine would then try and compensate by pulling timing and fuel which would keep making it shake and it could never figure itself out again until it's set for six or more hours.

 

Thank you so much for a reply, I will look into this as soon as I can.
I'm disabled so it may take a bit but I will respond if a solution is found!

 

One of the ways I was also able to confirm this was by measuring the ohms of each fuel injector, the one that was leaking and causing the misfire code was the one on cylinder 5 and it had significantly higher ohms than the other injectors all of which were outside of the oe range.

 

Okay. Hopefully this all works out!
Thanks again