Hi,
Possible other causes include short/open in wiring, faulty ECM, no or low voltage from fuel injection relay, or high resistance in EGR sv valve.
You will need to follow the flow chart below in order to diagnose problem:
Wiring schematics for doing above troubleshooting:
Automotive Repair Shop Manager
Automotive Repair Shop Manager, Technician/JA Mentor
An intermittent problem, such as loose/poor connection can be enough to set code but not enough to affect performance. This is reason i sent you the flowchart, in case you needed to check all connections and verify proper voltage.
You didnt mention that you failed to replace the EGR gasket. That is an important piece of information in helping diagnose a vehicle without seeing it. A leak at the gasket can be enough to set the code. Always replace gaskets when they are removed, you can never be sure of its overall integrity, including minute tears or compression from previous installation.
Let me know what you find.
Dont have an answer as to why the MAP sensor on that vehicle is so high. I looked around and cant find one for less than $220.