Would a cracked exhaust manifold on a 2002 nissan frontier 3.3 supercharged cause poor fuel milage

The rocker arms should be the same for Inlet and Exhaust. I can't find any spares supplier that differentiates.

https://www.enginepartsonly.com/1999-nissan-frontier-3-3l-engine-rocker-arm-ra616-35/

To tell which valves are Inlet and which are Exhaust, the exhaust valves are on the side where the exhaust manifold is.

https://www.google.com/search?q=1999+nissan+frontier+3.3+rocker+arms

Heads

https://advcylinderheads.com/nissan-frontier-xterra-pathfinder-quest-cast-owo-vg33-3-3-0-mile-cylinder-heads.html.html

..

Hi Jesse,here's a Autozone repair guide on your exhaust manifold. Repair Guides Engine Mechanical Components Exhaust Manifold AutoZone com

not a big deal, just use a wobble extension and take off the small bracket held on by 4 screws and use more than one extensins, use correct ngk and put new nissan wires too

Looks like about 21-35 ft. lbs. depending on which engine u have.

http://www.autozone.com/autozone/repairguides/Nissan-Frontier-Xterra-1998-05/Specifications/Torque-Specifications/_/P-0996b43f8037fa5c

If you need further help, I’m available over the phone at https://www.6ya.com/expert/michael_2496c4f07ad24453

code po105 refers to manifold absolute pressure(MAP)sensor/barometric pressure (BHARO) sensor -circuit malfunction==causes--wiring MAP sensor--BARO sensor--ECM
code p0171 refers to system to lean bank 1===causes intake/exhaust leak---AIR system MAF/MAP sensor fuel pressure /pump /injectors--HO2SW
code p0325 refers to knock sensor(KS) 1 bank 1-circuit malfunction====causes--wiring ---poor connections---KS
Check the exhaust flexible pipe at the manifold for cracks
have a fuel pressure test done on the fuel manifold to determine either pump/ filter or pressure regulator.
replace HO2S unit

Read your other post. 02 sensors is the cause

Defective 02 sensors will enrich the fuel and cause the waste. Supercharged the sensors are probably reading lean exhaust and screaming for mor fuel when it isn't needed. Good Luck, Ned-

It's stuck in 4x4.

Is it supercharged or not.Either way you will have to remove the intake manifold as it is in the "valley" between the two cylinder heads.

One of the common problem with 98 Frontier is crack exhaust manifold, take the heat shield off the exhaust manifold and check it for crack.