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Q: Broken timing tensioner pulley

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Drive home engine quit. Removed covers and found timing belt tensioner pulley broken off from mounting plate belt is still good. Should head be removed to check for bent valves or can this be done by removing valve cover?

My car has 90123 miles.
My car has a manual transmission.

Hello there, a broken timing belt tensioner pulley will cause big issues with your 1990 BMW 325i. When the timing belt slips or breaks it can cause the valve timing to get thrown off and the valve can hit the pistons, causing damage to both the valves and the pistons. In a case like this the vehicle should be inspected by a professional to determine to what extent the damage is and the best path to take from here. A qualified technician such as one from YourMechanic will be able to diagnose your timing belt tensioner and make any repairs required to get your engine running again.

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