Fixing Car / Steering / Pedal Vibrations (5)
Reason #5: The Engine & Gearbox
Symptoms may be sensitive to rpm, acceleration, deceleration or even occur randomly.
Worn out / Damaged Engine Mounts:
Let the engine idle, switch it off and restart it. If the engine appears to be shaking / moving in an unusually high manner, despite sounding like its running consistently, then your engine mounts need a replacement.
Inspect if the engine / gearbox mountings have deteriorated. Replace them with new ones.
Sudden vibrations from the engine bay area, which might stop randomly:
An unbalanced or loose cooling fan, or one with a broken blade(s). Vibrations will occur in a random manner, as and when the fan starts running.
Defective cooling fan clutch or A/C clutch. Switch on the A/C and observe if noise & vibration appear to be coming from the area of the compressor.
A misfiring engine creates vibrations in a random manner. The running of the engine will not sound consistently smooth. Search through Team-BHP to know more about the possible causes of an engine misfire.
While we've learnt the most probable causes for vibrations in a car, prevention is always better than cure. Please bear the following points in mind:
Listen (to) & learn (the) language (of your car).
Your car talks to you in a language all its own, and it's up to you to be able to interpret what she is saying. If you are a complete noob in this area, here's a fun link to listen to those sounds, and perhaps recognize some of them.
Tyre Treads Tell Tales.
An unbalanced tyre or wheel, a broken wheel bearing or an alignment gone bad....all of them will cause changes in the tread pattern of your tyres, even before your car starts vibrating (although misaligned wheels don't cause vibrations, they cause your car to pull to one side). Your ability to read the tyre tread pattern will preempt bigger issues in the future. Go through this useful resource.
Wobbly Wheels Won't Work Well.
If your car or steering start to wobble suddenly, slow down and stop safely. Check that your wheel nuts & steering linkage nuts are in place and tightened. I know of malicious people who have partially loosened the wheel nuts of badly parked cars blocking their driveway, and of tyre shops that haven't fully tightened wheel nuts after a balancing procedure. The consequences of one of your wheels flying off the car at speed aren't hard to imagine.