2000 Isuzu V6 Four Wheel Drive Automatic 113000 miles
My check engine light comes on when its cold and, when above 50, will not come on the next time I start the vehicle. It stays on when cold outside. The code that comes up is P0430 " Catalyst Efficiency Below Threshold.&Quot; It also has a P0300 Random/Multiple Cylinder Misfire Detected. Isuzu put in a new engine, under warranty, at 98,000 miles. I had to drive the vehicle with the blown engine (snapped a rod on a piston) for 115 miles to get it back home. I used quite a bit of oil during that time. Burned it off. My question is whether the P0430 code means that my catalytic converter needs replacing. If that is the case, could it have been caused by the oil burning when the engine blew. Gumming up the catalytic converter? If the CC is clogged, would that create back pressure that could cause the P0300 detected misfire? If the CC is clogged / damaged, should I also replace the muffler at the same time? What else should I replace. The new engine was a long block.