Not sure about pulling the plug wires to diagnose an exhaust leak, but to answer your other question, yes, a ticking valve can really be that loud!! I had one that was about 3x the clearance it was supposed to be (my own dumb fault) and you could hear it coming down the street from about 100 yards <img src="/forums/images/graemlins/ignore.gif" alt="" />

-1986 TOYOTA
22R
ZUK coil rear
Torqued T-Bars
Marlin HD clutch

Newly rebuilt!! Runnin' like a champ!

AZTTORA #492
TLCA member

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