What's wrong with my 04 Yukon 5.3l vin z? Check engine light on and flashes when engaging passing gear. I've replaced plugs wires air filter and fuel filter and its worse now? I'm baffled
Truck ran and idled fine now runs
rough after replacing everything
stated above right bank cat reads
almost 200 degrees hotter than the
right. What would make my truck run
Get the codes pulled then repost them back here and someone will help you further with diagnosis.
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