Car will start but will not stay running

Compression check was within spec. Did a leak down test, no issues. Brand new crank sensor. All wiring and connectors are good, no opens/shorts/etc. Haven't checked cam sensor but don't see why that would be an issue. I'm almost thinking I got a bad IAC when I bought the new one.

You can check the ops of an iac with it out key it on. You should see at least a twitch in movement. Also the cam and crank sensors have to talk to one another for proper timing. Great news on the compression though. At least theres not that problem! $$$ If this is a coil on plug car then check the plugs, the plastic lock tabs love to break causing a poor connection. Also check the timing chain for slop, you may have a stretched chain or loose tensioner/guide

Car idle is rough, now it starts won't idle without RPMs high. Computer code from Auto Zone said vacuum leak or oxygen sensor. Poorer mileage, doesn't run as well as before.

Your idle air control valve might really dirty also. It's located on the very front of your t/b & plenum on top of your engine. Those things will mess with your idle something wicked!

Electrical problem
1995 Ford Mustang V8 Two Wheel Drive Automatic 123, ++ miles

This Vehicle dies at any time idle. Warm, cooled at any rpm it has no spark no one could get codes. I worked on it for hrs. Finely got some codes (212) SPOUT look it up. ( Ground between EEC lV and TFI lV my question is where is the TFI lV and what is a TFI lV thank you for any help you can give