Check the EGR tube for vacuum leaks. Spray carb cleaner on the tube while the engine is running and see if the RPM changes

I am getting P1810. I have checked the PCM, all connectors and the such. Would you by chance have access to the troubleshooting flow chart for P1810? Or have any other ideas of what to check?

1810 trans fluid pressure valve position switch circuit

You can give this guide a try. https://www.gmforum.com/t279700/

i still get the p1404, car sometimes seems like its gonna die while accelerating, i took off the exhaust and car runs fine just loud no problems with car lacking par or seeming like its slipping runs like new, and the 420 i got before is also gone, only light i get is the one becuase ho2 sensor isnt hooked up, still get the p1404, not sure what to do ?

1404 EGR closed position performance

If the car runs good without the exhaust in place and wants to die with it on that sounds like a clogged cat. Can you see threw it? If not, replace it.

yeah cat was clogged thats why i was getting the 420 code, but without exhaist on everything seems fine but it still throws the p1404, and i dont know whats causing that , i replaced the egr valve, before i had a 440 i changed the vent valve n purge solenoid and that got rid of that one, only one left to figure out is the damn p1404

Display code I get is EXP 55

Any info as to what it means 2000 SEEi Bonneville

Thanks

All GM codes start out with a letter then 4 numbers.

B0500
P1404
U0743

Never heard of anything EXP 55, sorry.

I've never heard of a EXP55 code.

None of those codes come up on the display, only "Stability System Active" and goes off in a couple of seconds and then the "EXP 55" comes on for a couple of seconds and goes off, again the first thing that happen is the "low traction" light comes on, this whole process takes approx. 5 seconds as the car hesitates slightly as if the left front wheel bake was slightly applies or lost power.

When I had it scanned it showed loss of data communication with the Electric Brake control module

Thanks