Was this ever resolved??? I am having similar issues!!
Rough idle in drive. SOMETIMES Chevy Cruze 1.8L 2014 LS (65k miles)
I have had this car since about 35k miles has been great doing! All recommended maintenance was kept up to date etc. Then an engine code for the thermostat appears and that day seemed to be the start of all my problems HA. Replacing the thermostat and other due maintenance was in order..
After replacing the thermostat or honestly maybe even before said repair the rough idle began.
EVERY NOW AND THEN chunking and jumping like a wild big cammed car, putting the car in any other gear other than drive- the problem will go away.
On normal days it is not as smooth as brand new but fairly good. On good days she'll idle perfectly like straight from the lot. THIS IS AFTER REPAIRS MENTIONED BELOW
Super picky...(possibly the weather/angle of car/car temp)
Things I have noticed are- usually happens when the car is at optimal operation temp and it seems the idle RPM drops a tad when the shaking occurs and apply a little bit of gas will get the shaking to stop.
MAF/fuel pump/gas cap are next I guess with a extra eye on vacuum leaks/exhaust leaks?
MAINTENANCE(mostly OEM replacements)
~Thermostat/thermostat housing(cracked and was replaced with a metal one. Only part that I used that was not OEM. The Throttle body heater inlet pipe that sits on top of the thermostat broke so that had to be replaced. SUPER brittle)
~Valve cover(I found what seemed to be a pea size of oil (or fuel) on top of park plugs 2 and 3 replacement fixed this issue since)
~Spark plugs, coil pack
~Water pump(whining/possibly failing)
~Serpentine belt/serpentine tensioner
~Timing belt, timing belt tensioner/idler (heard a ticking noise from this side of the engine and got lucky the idler bearing was shot and when shook rattled. when replaced ticking went away)
~The entire air intake manifold(Had issues with the tuning valve arm coming off, then the actuator not moving so even went to the lengths of replacing the actuator before the entire manifold... This did not work as I kept getting NEW engine codes for the air intake manifold since its been replaced the code has gone away)
~The back VVT sensor (dunno why lol, hoping for blind luck?)
~Knock sensor(under the air intake manifold, why not)
~The coolant reservoir(cracked).
Motor mount looked in okay shape. MAF and throttle body have been cleaned. Fresh oil with no visible leaks/oil looked good when drained. No coolant leaks either after reservoir replacement (pressure tested)/also coolant looked good with the multiple times I had to drain it/bleed it. No engine codes. Do not know if a exhaust leak is present however... *
Definitely a beginner tree shade google mechanic so any advice would be appreciated.
Thank you!
