For cars that are older, there's a possibility it is cause by poor idling adjustment. Older car have carburettors, that would allow the adjustment of idling speed ( And the CO and CO2 mixtures).
For most modern cars, most are EFI( Electronic Fuel Injection ) that are control by ECU. Perhaps, in order to eliminate this problem, probably should have the mechanics to check if there could be any fault(s) to be found in the various sensors, such as; Throttle Position Sensor (Electronic control system is hunting (up and down) for the correct air/fuel mixture, and the engine would not respond to throttle input but to input by electronic sensors) and O2 sensor( ECU is constantly altering the injector pulse width, measured in the exhaust by an O2 sensor, in its search for the perfect air/fuel ratio).
Above may not be the complete solution to solve the above problem, hope it help in its little way.
Another idea is that the engine is missing (not firing or not firing correctly) on one or more cylinders while at idle; whereas an increase in engine RPM makes the missing unnoticeable...or to disappear (in the case of a mixture being compressed enough to ignite or ignite more efficiently before having time to decompress via leakage).
Possible reasons for the above might be:
1) Dirty/fouled spark plug(s) that need cleaning/replacing. (Broken and/or worn valve stem seals can cause the respective spark plugs to foul).
2) Burnt valve(s)...(from age, too high of a combustion temperature, inaccurate timing, or using unleaded in an older auto that requires leaded gasoline)
3) Blown head gasket. (Coolant entering cylinder(s) can cause non-combustion at low RPM, and not at higher RPM or non-combustion is not noticeable at higher RPM) (And/or compression loss via blown gasket passage causing non-combustion).
4) Cracked cylinder head. (Missing caused by same process as in #3 above except through passage of the head crack).
5) Cracked piston. (More unlikely).
Hopefully this has helped in giving some more insight. Vullin
Check your motor mounts. Have a friend eye the motor when parked. Apply the brake, put into drive gear, hold the brake and lightly press the gas. Try the same in reverse and watch for excessive twist in the motor.
Sounds like the engine mounts might be failing and no longer damping engine vibration.
not running on all cylinders? check for spark and compression on all cylinders perhaps catalytic converter is plugged
Bad PCV Valve.- Your car would vibrate a lot and keep stalling. if you try to floor the pedal in gear, the car will move but, vibration is bad and you'll stall again.
hi it sounds like your universail joints or tail shaft
If the automatic transmission car jerks when accelerating and the dash does not indicate a gear, there is a problem with the transmission. Check the shift solenoid.
gear ruber mount is broken makes the gear go down and up making vibration or souns like some is lose
most likely the cv joints are finished
maybe it is a problem with you 1st gear being warped because when ur stopped u are in 1st gear but park is a different gear
Variety of possiblities. The first item I would check is the center support bearing. It is in about the middle of the truck and the drive shaft goes into it. The rubber begins to give out and the bearing is no longer supported well causing a vibration.
You can tell when your car will take too long to shift to a higher gear when accelerating. Your transmission can also jump out of gear as well.
It may have broken motor mounts.
motor mount could be bad or broken
Possibly due to engine mount
Is ist possble to view the vibration specturm.
propshaft coupling is damaged
I think they all do this to a greater or lesser degree. Especially in high gear at low RPM. Really bad vibration might be the engine mounts.
The transmission is not shifting in and out of gear or your front joint is going bad
the cogs on the gear may be worn from abuse or just wear and tear. since first gear is used for pulling and other types of recreation you also may check the clutch plate in the tranny and clutch.
main shaft bearing
trans is breaking. get a new one
impala sluggish after second gear
could be the fluid level is low
that happend to me and my engine mounts where broken
First what type of car is it. rwd or front wheel drive? you can visually inspect depending on what type of car ,vibration while accelerating,cluncking noise when trans shifts gear 1st to 2nd mostly, this being the hardest shift under hard acceleration. or just take the vehicle to have the mounts inspected.