I have a high pitch noise, but it stops when I apply brake.
The noise comes from the engine area. I start the truck up. the noise starts.
It sounds like an electrical problem. I pulled all the fuses while the truck was
turned on. No thing happened.If i apply the brake while in park or while
driving the noise goes away. If I turn the truck off, the noise goes away but it
takes about 1-2 mins. Almost as if it was caused by pressure.
Could it be vacuum? Have you checked the vacuum lines, you referenced the brakes, so the first line to check would be the main booster supply line and check valve.
Search Toyota Tacoma Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Toyota Tacoma Experts