Sr20det starts, runs fine 2-4 seconds, sputters, then dies.

[ShaakeAanBake]

aI am running a sr20det red top with Gt2871R, JWT pop upgrade ecu, and supporting mods.

I recently replaced my clutch, full brake set up, and brake lines. My car had been sitting for 1 year and did not have any sort of problem before this.

I drove it for 2 days before this problem started. But, when driving for these two days. I had an intermittent problem with the car bucking/stuttering under 1/2 to full throttle between 1 and 3.5 thoundsand RPM. The second day when the car totally crapped out, It started stuttering around 2,000 rpm and I floored it out of aggravation and let of coasting downhill till I had to turn onto another road. When I turned onto the road and went to accelerate, the rpm dropped to about 1,000 stuttered as I blipped the throttle and died on the spot.

Here is the problem.

When I start it up. The rpm's go straight to 2,000 and it runs smooth for 2-4 seconds. Then it falls down to about 500-1000. If I try to blip the throttle to keep it running, the rpm drops to almost nothing then jumps back up to almost idle for a second and then back to almost nothing if it doesn't stall out. The TPS is working.

I have a professional working on it right now and he is stumped after trying a few things.

Here is what we have done, and nothing has changed. I replaced the distributor today, no change. I tried a different MAF from the same year 5.0 mustang although mine is from a Cobra, start it up without any difference. The fuel pressure is at 42psi, and doesn't fall off at all. Just sways between 38 and 41 when it is sputtering and then dies.

Just put in new spark plugs.

I found an unplugged wire today that is spliced into the yellow/red wire on the harness going into the ecu. It has a single male tip on the end. I'm not sure what this wire is for since I bought the car of someone who had the car built and doesn't know a thing about it besides what it cost really.

I think it is the MAF. But my mechanic is saying that when you unplug the MAF, the ecu should substitute it's own values or go to full rich and the car should be able to idle without it plugged in ????

Some one please correct me if I have been misinformed, as this problem sure seems like it is the MAF.

Any insight would help greatly.