1998 Volvo V90 6 cyl Two Wheel Drive Automatic 174000 miles
There is a high pitched squeal coming from below the rear passenger seats in the middle. The sound goes away when accelerating but returns once I let up on the gas. It stays even when at a stop. We tried fuel injector cleaner and thought it helped for a while but now the noise is back and a double dose of fuel injector cleaner didn't help.