2000 Xterra revs fine in park & neutral, only goes to 1500 in drive gears.

[Corbros]

My 2000 Xterra vg33e AT just had it's cylinder heads & gaskets replaced by me.

T starts, 400 rpm, light sputtering. I press gas, rpm stabilize at 1000. Can press gas pedal as hard as I want, the engine will rev all the way to the limiter. (neutral & park)

Shift to reverse. Rpm stabilize at ~700. No sputtering.
Shift to drive. Rpm still 700. Floor gas, rpm very slowly increase from 800 to 1200-1400.

Timing belt is installed correctly.
No engine leaks.
I don't have an OBD 2 scanner, so no codes that I can see yet, although the SES light is on.

Possible bad MAF sensor?

What are your thoughts? All out of ideas.

[ArmedAviator]

Get an OBD-II scanner and get the codes. Anything else you try to do shall be futile.

Also, welcome to NICO Club!

[Corbros]

I got:
P0115 - Coolant Temperature Sensor
P0325 - Knock Sensor
P0134 - O2 Sensor

And thank you!

[Desert Rat]

Might be in limp mode due to one or a combination of codes.