Need advice on Chevy 8.1 Vortec engine (2003)
We have experienced loss of power going up long steep grades. and the engine light on. 3 times. After the second time , a truck service repair said the 02 sensor (bank 1 & 2) probably came on due to...
Forum Discussion
We've been through Moab many times with our 8.1L engine and at a little over 4000 feet in elevation, the octane of the fuel would not be a problem. Since the O2 sensor was changed, that should eliminate it as the problem, unless the lead to it came loose. A bad O2 sensor usually results in very poor fuel mileage as well as the check engine light coming on. Your exhaust pipes also would probably be black from running rich.
I would try to take the coach to a place that can check your emissions. If either the MAP is dirty/bad, or if one of the sensors is bad, it will show up in your emissions being well out of spec. If the shop does not have the capability to check emission, the best they can do is throw parts at the problem, at your expense, and see if a test drive feels different from the last test.
Keep in mind that the 8.1L engines, in SOME coaches, had a problem with the rear spark plug wires deteriorating, due to heat. This can also cause a loss of power if one or more cylinders are not firing properly, which causes your engine computer to try to adjust to the situation. If your coach is one of those where the manufacturer did not allow enough air flow it may mean that you will have to install a set of high temperature silicone plug wires, like the Taylor Extreme silicone plug wires with the additional heat shield.
I would try to take the coach to a place that can check your emissions. If either the MAP is dirty/bad, or if one of the sensors is bad, it will show up in your emissions being well out of spec. If the shop does not have the capability to check emission, the best they can do is throw parts at the problem, at your expense, and see if a test drive feels different from the last test.
Keep in mind that the 8.1L engines, in SOME coaches, had a problem with the rear spark plug wires deteriorating, due to heat. This can also cause a loss of power if one or more cylinders are not firing properly, which causes your engine computer to try to adjust to the situation. If your coach is one of those where the manufacturer did not allow enough air flow it may mean that you will have to install a set of high temperature silicone plug wires, like the Taylor Extreme silicone plug wires with the additional heat shield.
