[gazzerr]

I think it's more of a risk with the earlier cars (pre 81?) that don't have the metal spider in the airbox. You risk putting extra unburnt fuel into the intake chamber that all the runners connect to so there's a chance you could flash it off and blow up the airbox. A CIS that's working properly doesn't need you to touch the pedal to start it. If the CIS is not functioning properly then there's always the risk of a backfire that could toast the airbox. I've read here that the pop valve can actually leak from a previous backfire cause a lean condition and then cause another backfire which can blow up the airbox too!

The fix begins with checking fuel pressures to determine the condition of your warm up regulator (WUR) and checking for vacuum leaks. After 30 years the glue holding the airbox together fails and they leak, causing what you describe as well. It's quite possible your car has had a backfire or two in its history and the airbox is leaking from that. Search for "CIS for Dummies". It's the go to thread for re-conditioning your CIS.