2000 Ford E-450 6.8L V10 (motorhome). The motorhome is in great shape, the engine runs strong and amazing, but I can't pass emissions right now. I keep getting misfires on different cylinders. I was also getting a lean code also. I have replaced the following:
New Spark Plugs 10
New Plug Boots 10
New Fuel Pump 120 PSI
New Fuel Pump Filter
New Fuel Tank Breathers and hoses
New Fuel Filter
New Air Filter
New O2 Sensors
1 year old Catalytic Converter
Well here's the thing if your engine runs really lean you will get misfires bouncing all over the place. It won't be just one. It can be one and then a different one and then another one because running lean makes an engine misfire. I would start by trying to figure out why it's running lean. It could be a bad fuel pump. Could be clogged injectors. Could be leaking intake manifold. Try to figure that out first
