Whining noise when accelerating ... (another case)

[brightsun]

I'm sure there's a similar post in this forum, but my situation is slightly different on the Montana '03 (almost 80,000 km) that I have.

When I'm accelerating from 0, the whining noise starts to kick in at about 40km/h & getting louder as the car goes faster. If I brake, the noise "whines down" & become unnoticeable when the car is less than 40km/h or idle.

Note that the whining noise is not heard either when I hit the gas pedal in the 'Park' mode. The noise persists even if I turn off the A/C ventilation fan.

Could it be that the spark plug(s) in some of the engines misfiring ? Or transmission ?

Any ideas ?

[brightsun]

Alright, I found the problem: the passenger side's front bearing is damaged a few months ago (due to either curb hitting or an accident) & the condition went unnoticed until now, when the damage has extended more & become audible ... I guess some balls in there won't last too long with this noise so I had to have it fixed immediately. I roughly posted the procedure here (message #7).

Tip to diagnose the problem: if you're running at high speed (>40-50 km/h) on a straight line, try to juggle the steering wheel a little (make sure the street condition is SAFE before doing so!) & listen to the whining noise.

If the noise lessens when the steering wheel being juggled then the bearing is the cuprit.

If the noise remains the same pattern, it's the tire.