Yesterday, one of our 100s suffered a misfire at 3000, wouldn't pull above that and ran slightly rough once falling back to idle. Did air/fuel filters, throttle body, air flow sensor etc. No joy. Seems an impact dislodged the LH O2 Sensor lume and it suffered heat damage on the Cat pipe. As a result, two wires had fused, resulting in blown 10amp Emission control Fuse in LHS front fuse box #36. Bit of soldering, new fuse, done.