Ok so I have a 79 4x4 with the stock carbed 20r. The carb was just rebuilt 3 months ago but I have this bad afterburn every time I shift the truck. The truck has been sitting since 04 when we bought it a couple months ago. For exhaust it has the stock manifold and it goes to a glasspack(which is probably burnt out anyways) there is no cat converter. If I had an actual muffler would that solve the problem? Or is the problem something else like the fuel cut off solenoid? By the way it looks like mine is vacuum operated, google shows everyone else has a vacuum switch that controls an electronic fuel cut off....here are some pics i snapped earlier. Is this the wrong solenoid? Anyway to fix the afterburn? Thanks guys Still has all the smog stuff on it if you couldn't tell by the mess of vacuum lines lol