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1999/2000 Itasca Sunrise Class A Motor Home with 7.4 Vortex 454 Chevy Engine
Experiencing Very Bad Running Conditions
The basic problem is this:
When we start out in the morning, the engine seems to run fine.
After a short while, it loses power and even though gas pedal is to the floor, it will not get above 50-60 mph, (even downhill)
Loud and intense backfiring thru exhaust on de-acceleration
If we keep driving, sometimes it reverts back to running ok
All 4 plugs on Bank 2 are constantly fowling out, within less than 100 miles
Had it scanned several times, and it reports multiple codes ... sometimes says running lean, bank 2 ... other times it saves 02 sensor shows no activity