There is a noise when the steering wheel is cranked and you accelerate on my 91 AWD Previa.
At first I thought that it sounded just like a CV joint but they seem to be pretty tight. Normally there is no noise while driving. It is recently purchased with 128,000 miles. Other than that it runs great and it drives well.
if you hear this noise coming from under the hood, then check your belt or alternator bearing.
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