Sluggish and slow acceleration

Hi,

The negative trims indicate the computer is trying to lean the fuel mixture. Have you checked fuel pressure to make sure it isn't too high? Also, are there any strange odors coming from the exhaust or rattling sounds? The catalytic converter may be plugging.

Do me a favor. Take a look through this link and let me know if it mirrors what you are experiencing:

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms

If it does, take a rubber mallet and tap around the catalytic converter to see if anything sounds loose inside it.

Additionally, checking for diagnostic trouble codes can be extremely helpful. You mentioned the fuel trims, but are there any codes present?

Also, if you haven't check fuel pressure, I recommend it. Here is a link that explains in general how it is done. Additionally, the attachments below are specific to this vehicle for fuel system diagnosis. Pressure may be too high due to a faulty regulator.

If you are questioning the catalytic converter, remove the upstream oxygen sensor to see if it changes how it runs. That will allow additional air to escape. Or, here is a link that shows how to check a catalytic converter:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Let me know what you find or if you have other questions.

Take care,

Joe

See pics below.

No bad odors. There is a rattling noise. Hard pinpoint, sounds like coming from back of engine area when i raise the hood. Passes smog check on scan tool. No codes including pending codes. Fuel pressure around 50 PSI. I've noticed O2 sensor 2 doesn't switch up and down between .1 and .9 volts like sensor 1 does. O2 sensor 2 stuck at .7 volts. Intake manifold between 5- 29 HG. Mass airflow 0 - 20 lbs. Air intake temp 39-100f. Coolant 216f. Cat temp 1200 to 1500+ during driving, 800 at idle. Bar temp 29 Hg. Evap pressure - 3 to 0.6 fuel level 49 - 89. Air intake temp sensor 1 82 - 88, Sensor 2 102f.

What you are hearing in the rear of the engine could be the converter. They can come apart inside. As a result, they can block the exhaust and then move and allow normal flow.

Take a rubber mallet and see if that is where the sound is coming from.

Let me know what you find.

Joe