I have a 86 Vette 100% stock ,low miles took it for Saturday cruse.It was idling about 1100 and hunting,and a noticeable knock@ WFO.
Pulled in and raised the hood found the grommet on the valve cover to the throttle plate cracked ,
I had a new one put it on and Walla back to normal
? is my Buick has vented valve covers with a vacuum leak all the time and its just fine,dose the TT chip adjust for the leak?