I have a 2005 5.7L autozone tells me check engine light is for multiple misfires. Had problem before and dealership told me someone put the oxygen sensors on backwards. They checked the electrical system thoroughly before they came to this conclusion. Now problem is back and getting worse. Any ideas?

 

02 sensors are not going to cause a multiple misfire code

Did you do anything like shorty wires, etc?.

 

ya when i installed the shortys i started have misfires under modderate acceleration. new plugs fixed it

 

No I have not replaced any wires . the dealership checked the spark plug wires before they came to the conclusion that the o2 sensors were backwards