Hi,
I recently bought a second hand Automatic2002 Honda Accord V4... it has been driven about 186,000KM.
But recently I have noticed that the car is giving off ridiculous amounts of vibration.

This mostly happens when I stop the carat a traffic light, or wherever and the car is still in Drive, withintwo seconds the car begins vibrating and the entire front panel of the vehicle vibrates like crazy, the steering wheel and dashboard, ALOT.
While driving, the car moves smoothly with barely any vibration.

Though I have noticed that if I put the car into neutral, it suddenly stops vibrating, as well as in "2" and "P". I tried the vibration differences in D4 D3 2 and 1, the vibration only stops in D2, N and P.... Remembering this only happens when the vehicle is stopped.

Also, i've noticed that when I turn the AC on higher, the cars vibration doubles/triples itself, and suddenly slows down/stops when I close the AC.

Why is this ? Anyone have any idea ?
Don't want to have to pay a mechanic 100$ just to look and point out a minor problem, if someone can help me out please.

Thank you.

 

Sounds like a bad motor mount to me

 

I would agree.

 

yup ..... I think it would be the rear lower mount ..... if the vacuum chamber got messed up in there, it would cause what you describe. Do you also get a small wheel hop when the car shifts 1 to 2 or 2 to 3 when giving a moderate amount of gas? That symptom would make the mounts seem like a definate thing. The problem with the rear is that it's an easy thing to change, but the book says that it's worth $200 in labor. From underneath the car, it's just as easy as the front one. Right before my tranny died, I changed all 3 mounts. The parts cost $70. I think I got them from TAS, but I'm not sure.

 

Do the idle rpm drop when the vibration occurs? If so then I suspect the IACV (a valve that compensates for auxilliary loads on the engine, keeping idle at the correct rpm) isn't working properly, or the base idle is way too low and the IACV is having trouble compensating for that when an auxilliary loading is placed on the engine (base idle speed is set with no loads on the engine and the IACV disconnected, so that with the IACV connected it doesn't have to anything until the idle rpm drops).

An auxilliary loading is caused by things such as using the air-con, high electrical loads (which cause the alternator to work harder, placing a load on the engine), or by the transmission being in gear (a 'dragging' load on the engine through the torque converter). If the IACV isn't able to allow an increase in air flow past the closed butterfly valve in the throttle body (or can't increase idle air flow enough), then the load will cause the engine idle rpm to drop, causing vibration.

My first check would be to check the base idle speed. If you disconnect the electrical connector then the idle speed should remain the same or drop only a bit. If it drops a lot then the base idle needs to be adjusted. If adjusting base idle doesn't fix the problem then have the IACV cleaned out. Cleaning the throttle body internally might also help. These thingsmight fix your problem.