My 2007 Altima , automatic revs too high.

Just remove and clean the IAC valve and replace if necessary...

replace your accelerator cable.

May need to replace temprature sending unit. Car doesn't know it'swarm.

The engine light indicates that there is a Diagnostic Trouble Code (DTC) available for download from the vehicle computer. Go to your local Auto Zone or O'Reiley's (SP?). They can download the code and tell you whats involved and its FREE!

this may be a problem with the tps sensor

No real answer to the first half of your question, but I do know that when you are revving the engine to 5,000 rpm in neutral you are hitting the engine's rev limit. It is most likely not related to your original complaint.

put in neutral, and neutral on 4wd tbar. rev motor to 1500rpm, put in high 4wd, let it click in, then low 4wd, then in 2wd.

theres many things that can be the cause,instead of having people tell you to try this and that,change this and that,scan codes it will point you at problem area and start from there

check your motor mounts, do this by opening the hood and pushing the car back and letting it rock, if the motor moves more than an inch either way, your motor mounts are bad.

sounds more like the IAC, Idle air control valve.. they can be cleaned with carb and choke cleaner gently...