Can anyone tell me where the Map (Manifold absolute pressure) sensor is located on the nissan titan (2005). If its on the firewall I haven't been able to find it. Also checked on the manifold. I appreciate any help

Look on top of the throttle body--likely has a 3-P connector going to it. If it's on the firewall, look for a vacuum hose running to the throttle body.

I believe that model uses speed density by calculating air flow combined with intake air temperature and throttle position.
Are you getting a check engine light or any other drivability symptoms?

It looks like you have a Mass Air Flow Sensor:

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Look on top of the throttle body--likely has a 3-P connector going to it. If it's on the firewall, look for a vacuum hose running to the throttle body.

I appreciate the help everyone, I have checked the throttle body and it isn't there. Would it be at the end of the vacume line or closer to the throttle body? I know where the maf is , I just can't locate the 3 (sometimes 4) prong Map sensor... is it possible the truck doesn't have one? I appologize for my ignorance and appreciate the help.