Engine noise and car stalls

The tapping is the valves hitting against the buyer upper part of engine. The stalling is most likely the computer shutting down engine. You might have engine damage. The tapping comes and goes according to engine rpm the higher the rpm the louder the tapping. If I was have it towed to u mechanic and have them run test engine might be beyond repair

The check engine light will come on when the management computer detects a fault that can affect exhaust emissions. When that happens the computer switches to a get you home programme and records a fault code.

A code read is required to discover the fault which should then be verified by independent tests before wasting money chasing down blind alleys.

Loss of power, but no mention of rough or inability to idle (including stalling). If those additional symptoms are part of the problem, check for a vacuum leak to the intake. Listen for hissing or sucking noises near air hoses. Look for loose, cracked, or broken air hose connections. Check PCV valve...Cheap to replace, could be sticking, then loosen after truck sitting with engine off. A vacuum leak will not give any light indications, and vehicle will seem to run normal when applying gas, but will want to stall or run rough (or want to stall) when at idle or sometimes when taking foot off gas when slowing down.

bad seatbelt connection

My 1987 buick centry limited cuts off when i drive but when i start it back up it will start right bacc up at times some times it starts and die agin but when it dies the battery light and service engine light comes on but once it starts the service engine and battery light goes away and dont do it agine tell it cuts off agine

try the EGR valve. replace it or clean it the EGR ports may be clogged as well

try changing your tps sensor

have the car checked when the check engine light is on,also a good scanner will be able to give you the history codes,get back to me with the codes and we'll go from there. you need someone with a professional scan tool

trotel position sensor

the white smoke as it stalls could be steam in the exhaust. This is caused by coolant leaking into cylinders from a leaking head gasket. You should check cylinder compression next with a compression tester.