Well, this should be my 25,000th post to the board. I was wondering what my first post to the board was. So, I checked the archives. As far as I can tell, this was it:
August 8th, 1998, 11:28 AM
Joe Lucia (12484)
Beyond Control Poster
Join Date: January 31st, 1988
Posts: 24,999
Re: Back-firing LT1!!!!
re back firing lt joe lucia another possibility is a defective a i r diverter valve you can check for this by removing the belt from the pump and disconnecting the vacuum line which provides the vacuum signal to the valve from the carburetor if this resolves the backfire problem you've found the cause another possibility is a defective ignition coil

Joe Lucia (12484)

Beyond Control Poster
Join Date: January 31st, 1988
Posts: 24,999

re back firing lt joe lucia another possibility is a defective a i r diverter valve you can check for this by removing the belt from the pump and disconnecting the vacuum line which provides the vacuum signal to the valve from the carburetor if this resolves the backfire problem you've found the cause another possibility is a defective ignition coil
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