what do i have to replace to fix the tapping and poor performance . 88 cougar valve lash
New valves, heads redone. If you can have it done cheep, then do it...If not the repair will be more then the car is worth...
Could be the knock sensor is picking up the valve tap and severely retarding the ignition timing. If it lacks power, runs hot or boils over, and the transmission is shifting late that's what I'd suspect. Disconnect the knock sensor(s) and see if that improves things. If you have a knock sensor module disconnect the knock sensor wire there so it won't trigger the check engine or service engine soon light. I had to do that very thing with my '93 Caprice once it developed a valve tap. HTH. -Jim
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