Problems with car shaking.

I recently took my car to a mechanic in my area, and got the ignition
coil/spark plugs replaced, due to a shaking/shuddering while
accelerating. After the work, the acceleration problems stopped, but
a faint shaking I had continued. It has steadily gotten worse, and
I’ve taken it back to the repair shop (STS) and been told that they
can’t find anything wrong with it. I’m tempted to take it to another
mechanic, possibly at a dealership, and have it looked at again, but
I’d like to get some insight as to whats wrong if possible. The
shaking gets worse after the car has been running, usually after 5-10
minutes when the car has warmed up. It only really shakes when idle
(at lights or stop signs), though I think I can feel it slightly when
driving. Shifting from anything in gear to parked makes the shaking
stop, or at least become a great deal less noticable.

I am fairly clueless when it comes to cars, so if there is any
other questions you can ask me to maybe narrow it down, feel free to
do so. Thanks for your help!

 

What year, model, and engine do you have, EricC?

 

2000 Hyundai Sonata, and I’m fairly sure it’s a 4 cylinder engine

 

I too have the same problem, I have a 95 hyundai elantra, but the
problems you are exactly like mine. I wish I could help, but I don't
know either what could be causing it. The shaking has gotten really
annoying and I know it is bad for the car. If there is anyone out there
that knows what is please share the knowledge. Thanks.

 

The four cylinder Sonatas have some noticeable vibration in gear when
idling that's normal. It's usually most noticeable in the steering wheel
and is often worse when the a/c is on. If you have any doubt as to
whether it's normal, stop by your local dealer and have them look at it.
They should be familiar enough with your particular year and model to tell
you.

 

My 95 Elantra shakes too. I'm planning to replace the motor mounts soon.