CarmonColvin

Now that I fixed the injector problem I was able to get the car to start up with out starting fluid. But at first it would only catch with NO throttle and once running it would rev to 1500 rpm then immediately die (sometimes backfiring when RPMs drop). But as soon as I hit the key again it would start back up and do the same thing.

Loads of people told me it was a vacuum leak. I searched and searched and I could not find one. The metal vacuum spider has been removed and every known vacuum port not used (only going to secondary throttle plates and fuel pressure regulator) have been capped. Just to make sure it was not another fuel problem I checked the signal at the ECU on the injectors and confirmed they were trying to fire until the motor stopped turning. I then checked the fuel pump again and it was running up until the motor stopped turning.

On the idea that the motor was getting more air than it knew about through a vacuum leak I propped open the AFM and tried to start it. It started right up and remained running. After about 2 minutes I allowed the AFM to go to its natural state and the car remained running. Another minute went by and I let go of the throttle cable (I had been holding it to around 2500-3000 rpm) and I expected the car to die. But it dropped to a ~1000 idle and remained running. The idle was by no means smooth, but I played with the timing and got it to run a bit better. I believe part of my rough idle is from the heavily ported engine so I was very happy with the way it was running. I allowed it to run for around 10 minutes before I shut it off, to check the oil and such. After that it started right back up with a decent 1000 rpm idle. I backed the car out of the garage and allowed it to idle for around 45 minutes (part of the new engine break in procedure).
I constantly monitored the oil pressure and water temperature and everything was great during this time. The only thing I noticed was around 30 minutes into the idle session the quality of the idle began to decrease. It was missing a bit more and the rpms would drop to around 500 rpm and then slowly climb back up to around 1000prm.
I then took it out for a short drive keeping the PRMs down. Twice it died when pulling up to stop signs and by the time I got back to the house it would not idle at all.
I changed the oil and tranny fluid and did not start it again last night.
This morning I go to try and start it again and it was doing the same thing as before. Start, rev to 1500, die.. over and over.

It almost seems my vacuum leak seals itself up when the engine is warm but what explains it not wanting to idle after 30 minute of being at full operating temp?

FPrep2ndGenRX7

Might be the AFM acting a little screwy. I've got a spare if you need it.

HAILERS

Inside the afm there is a micro switch. When this switch is made, it provides a circuit to the fuel pump for it to run. The switch is made when the flapper door in the afm moves to open.. The only reason the fuel pump runs when you first turn the key to start, is because that action temporarily pulls a relay in to provide a circuit to the fuel pump. Let go of the key....no fuel pump. By the time you let the key go from start to on, the afm door should be making the switch to make the fuel pump circuit. So the afm door switch is letting you down. A work around for this is to jumper the yellow fuel connector on the r/h strut tower. That by passes the switch in the afm. Makes the pump run all the time if the key is to on. I'll bet the switch in the afm will start to act right after the engine gets some time on it. I think it might be a little sticky right now. The above should explain why the car started and ran when you propped the afm door open.....micro switch was made completing the fuel pump circuit.

CarmonColvin

I am positive that the sensor/switch in the AFM for the fuel pump is working just fine. Even when it just runs in it small rev to 1500rpm before it dies the fuel pump is getting power and the fuel rail is getting pressure up until the motor stops turning.

I am more leaning towards a vacuum leak that fixes itself when the engine gets warm. And I assume that the plugs got fouled and that is what caused the rough/no idle after I drove the car.

Tonight I am going to use my shop-vac/blower and try to pressureise the intake system and trace any leaks with some cigar smoke. If that does not turn up anything I will be at another dead end of ideas.