After years of giving no fucks, maybe it is time to start giving a few. Our trusty steed here backfires every time the engine first starts and then randomly off and on as you drive. With a car engine I’d start by looking at spark and timing, but I don’t know where to start here. Thanks in advance (no pun intended). It is an overhead valve engine, probably around 300cc. It’s done this before, and it mysteriously went away, but now it’s back. Oh hey look it’s Project Deathtrap in the background, where it hasn’t moved in over a month now. We rigged up an ignition button under the dash of the Acura to bypass the broken key-switch so there’s that at least.