Hey I took the car out for a quick ride today to get thigns moving from the cold, and all of a sudden some real loud pops started coming out of the exhaust... The RPM's kepts fluctuating from 1200 to 1700 RPM...I know the car needs to be tuned because the halltech air/fuel was reading rich to the max, but I was worried when it would drop all the way down to lean.... I just started the car up again and everything was pretty normal no popping or shaking...

What do you think it is? Just a tune or something more serious? It has a single with a new untuned ported engine

 

It's called backfire. Unburned fuel in the exhaust. Needs tuning.

 

thanks for that reply PmPn