Not necessarily bad for the car but when the AC is on, it causes the engine to work harder which you will feel as the compressor cuts in and out. This is normal. A parked car with the engine running is generating a lot of under hood heat as opposed to when it's moving and air is moving through the radiator to cool the engine.
Not really. When parked, the car is idling, as slow as it will go smoothly, and the A/C is just a little extra load. And the cooling fan for the engine will have to run as there is no breeze from the motion of the car. Both of these are minor (very minor) strains that cars are engineered to experience.
When your ac compressor turns on the vehicle will idle higher and will generally use more fuel while in park, the shaking however if noticeable and noisy it may be that something is loose or perhaps that your engine mounts are getting older and the extra load on the motor causes a bit of vibration when the compressor kicks on and off.
on low torque engines, that can be somewhat normal. on higher torque engines, it's likely a matter of a tune up or induction/emissions systems and component cleaning that's needed.
and this qoute "the car will shake a little bit randomly"
"....randomly"
fits the tuneup/cleaning scenario.
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there are a few platforms that i would not do that to. known for cooling issues. taurus/sables with small grille openings, and some older full sized mazdas. specifically the 929's. and many mopar mini vans.
if you do that, do look under the vehicle to ensure all under belly pans are up and flushly mounted. on many platforms, those pannels aid in directing air flow through the radiator.
another issue on that is the condition of the coolent. fresh antifreeze mix keeps engines cooler as well as keeping them from freezing. as heat can be xfered easier with an antifreeze mix as apposed to plain water or weak/old antifreeze.
It's not unusual for a car to do that. The air conditioner is putting extra load on the engine, which is already down to idle speed and trying to burn as little gas as possible. As long as the engine temperature is not going up, it's OK. Not good for the engine, but not really bad for it, either.
it isnt bad the car shakes because the engine must also turn the AC compressor and it may shake a bit. depending on the car just running it while parked may overheat it after a while..
I've noticed that when the car is in park and the air is on, the car will shake a little bit randomly. Is this bad for the car?
