My car has been at the paint shop for a year. It ran perfect. Now, you start it fine and then it dies in 2 or 3 seconds.
We checked power to the fuel pump and it wokrs, loses power then dies then power comes back to relay... Have not checked any others.
Please help! I really want to drive my car after a year of waiting!!!

 

Tell us a little more about your RX-7 brandynmarie. What year? carbureted or fuel injected, manual or Auto trans, turbocharged or not?
You say that you are getting power to the fuel pump. Is fuel pump getting power all of the time when running or does it lose power and then engine dies?? What relay did you check?
Will engine continue to run if you are spraying some starting fluid into the intake after starting up normally?

 

The problem is in your Mass Airflow Sensor. Check to make sure that it is plugged in properly and that it is functioning correctly. The car is programmed to run the fuel pump for 2-3 seconds on startup then switches to readings taken by the Mass Airflow Sensor. When the Mass Airflow Sensor opens and begins taking readings, it completes a ground type circuitthat is needed for the fuel pump to run. If everything is plugged in and operating correctly, you can go one more step to see if there are internal problems. There is a brown wire (no stripes) that goes into the connector for the Mass Airflow Sensor, run a short jumper from the back of the connector to a ground (body or engine ground doesn't matter). If you car now runs for more then 2-3 seconds, you either need to fix the Mass Airflow Sensor or replace it.

It's possible that while at the paint shop something got unplugged or bumped or the gate inside the unit got gummed up or something like that...

 

No AFM unless you have an '86 & newer.