Hello, is the Check Engine light on? It sounds like you may have either a fuel pressure/volume issue, or a clogged Catalytic Converter.
To do a fuel pressure test on these vehicles, they want you to remove the fuel pressure damper from the Fuel rail and screw in a fuel gauge at that point. I'll post the instructions. Since this test takes a lot more time, you can try removing one of the front Oxygen sensors and see if the vehicle will rev any higher, if the Converter is clogged removing one of the front oxygen sensors will relieve the exhaust pressure that is building up. It will be loud, but this is the location for doing a back pressure test because it is before the Converter.
With the oxygen sensor out, you should notice a difference right away. The sensor will probably be covered in soot as well. So will the spark plugs. Here are a couple of guides to help.
Also do you notice any noise from the exhaust, or any rotten egg smell? Those are also sign of a failed Catalytic Converter.
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Sunday, December 4th, 2022 AT 12:00 PM