97 Acura Cl 3.0 liter 260,000 km's.tranny recently rebuilt,first time.
I've had a vibration for quite awhile while idling.I changed 3 of the motor mounts and was about to change the Idle Control Valve when i discovered the vibration was caused by my rad fan.Someone sitting in my drivers seat felt the vibration and it coincided with the fan coming on.I bought a new idle control valve and when i put it on i had that fluctuating rev flutter from 1000-2000 rpm's.i didn't have that before with the old one so i think i got a defective new one.could it just be the fan?the blades?the bearings?if anyone else has had vibrations see if it happens when the fan comes on.Will a good ICV even out the revs when the fan comes on so there won't be that vibration?
Any thoughts,ideas or solutions will be appreciated.
Thanks.

 

Ive personally never seen this issue happen, but with a new ICV, are you sure you put it on correctly with no air leaks? Sounds like the fan is dropping your RPM's to the point of causing cabin vibrations when it comes on, like when the A/C comes on. Make sure your RPM's are staying where they're supposed to, and that the fan is sitting correctly and double check your ICV install. Hope that helps

 

Thanks DaInFaMMuS1.Is it possible that it's not the ICV?Could it be throttle body?TPS?I just had the EGR ports cleaned and the injectors redone with seals and filters.I ordered a replacement ICV.I'll try that,again.

 

if the bearings in the fan are bad they can cause a vibration, its usually accompanied by a noise to but you never know, or the fan could be causing something elce to vibrate due to harmonic resonance, again failing bearing.

as for the ICV, sounds like a leak, check the gasket seal, to see if its a bad part try putting the old one back on and see if it goes back to how it was. i just cant see the ICV being the vibration problem for the fan, i think you found the problem (fan & vibration) and are looking too far ( sensors and engine), just sayin.

well , good luck.