my sisters bronco is in the garage having its alternator belt and power steering belt replaced. and i got them on all tight turned on the bronco and it was making this screaching tugging grinding creepy noise as it was on and first i thought maybe the belts are just squeelin so i took them off and still that same noise. and as i shut it off i heard a pressure being realeased from the motor and it sounds like it on the driver side and towards from the exhgaust manifold. can someone help?? its a 89 ford bronco 2 4x4 2.9liter

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1989 xlt 4x4 "problem child" ranger
2.9 ltr KnN cold air intake, 88 2.9 throttle body
jvc stereo, kicker speaker 6x9s, 2 12 kenwoods with 1000 watt kicker amp and 4 gauge wiring. 153.2 decibels. My baby the Ranger

Are you sure the starters not sticking in and running with the engine.