Truck Repair: 5.9 cummins 12 valve, laser thermometer, rocker arm

Question
my 96 5,9 cummins is missing and kind of popping out the exhaust and kind of sounds like a broken rocker arm (on small block chev)  

Answer
Hi Craig,
check if you have an exhaust leak at the manifold first...if not then pull your valve covers and see if anything is ok. if so it may be possible that one of your injectors is not firing...check all the wiring under the valve cover. If you have a laser thermometer, run the engine up to temp and take a reading at each port on the exhaust manifold. if you have one that is way cooler than the rest it is a pretty good indication that that injector is not firing. don't just replace the injector...find out why it isn't firing first.

good luck

matt