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Re: Enging started ticking after a backfire
What the other guys said. Also...
Back in the late 1980s I had a 350 running at low speed (2800 rpm) under heavy load (WOT) on a dyno while doing some knock work with regular fuel -- we were trying to make it knock and figure out what spark timing would make it knock at different octanes, measuring torque to get BMEP, and cylinder pressure to get IMEP and knock frequency and everything. It made some loud backfires and then started missing. After compression tests it turned out that one cylinder had overheated/bent/warped an intake valve. It was visibly tweaked and not sealing on one side. I was not revving it, so likely no piston contact. But the valve head was canted just enough to not seal. I bought a new valve from NAPA for probably around $10 (30 years ago), touched up the seat with the just one stone of the seat grinder (not 3-angle), and I was back in business.
I have not seen that failure mode since then, but I have also not done heavy knock work since then.
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