Won't rev past 2000 rpm

Plugged catayltic converter .

Clean throttle body,change air filter,then could be IAC sensor next TPS sensor(RPM).

do you have fuel lines near any hot surfaces like manifolds? sounds to me your fuel is getting hot and vaporising. Try fuel pump or relay. Coil or igniton module next most likely.

the crank sensor is favorite they are unreliable that explaines why the trans not getting engine speed signal unless its a manual box and that code will allways be logged advise start by checking for water ingress in engine control module located lower rh a post then change crankshaft position sensor or better still try and borrow one from a good running car

While your car is running.......pop the hood and find the throttle body. The throttle body is where your air filter tube/hose goes to the engine. Locate the throttle position sensor which should be on the side of the metal throttle body. This should be the item causing this. If you grab the plug that is on the sensor and wiggle it while the car is running then the engine should rev and act up if thats the problem. If not let me know and I can direct you further. Thanks.

first try using redexe fuel additive (a full bottle to 5gallons)to clean injectors/fuel pump.
your car has a fuel cutoff valve,saves fuel when coasting(over 1800 revs,if you put car in nuetral going down hill you use fuel,so you are wasting fuel in neutral.but you have read the handbook cos it tells you in there.......

disconnect the throttle cable from the throttle body and try to rev the engine

if still cannot rev past 2000 then suspect MAF (mass air flow sensor) or the throttle body...remove the snorkel and check to make sure the throttle plate is moving freely

finally, if when the accelerator cable is removed and rpm's rise above 2000 then suspect the accelerator cable and/or gas pedal

check the mass air flow,and the tps sensor

Check fuel and air filters may have gotten water in your fuel

you may have two oxugen sensors on your yukon. if so the oxygen sensor that controls that bank may be bad. from what you mentioned in your complaint, it sounds like it is the oxygen sensor.