So everything was fine and now it will not stay running for more than a minute , whether in gear or not. I can hold throttle open to steady 2000 rpm and it will just drop out. I have replaced iat sensor , cap and rotor, coil , fuel pump relay and harness. Plenty of fuel appears to be dumping in tbi , it will just stop about 45 seconds after running.
What is next?

 

When it fails again, check if you lost fuel or spark. My guess it will be spark, then it nery well could be your ign. module.

 

I think your on to something. I pulled the cap again and pulled the module it it was pretty corroded. The two wires- green and white that connect - plastic plug disintegrated . I picked up a new module , but need to figure out a repair on the plug.
Thank you for the advice

 

So ignition module is changed. Now it is idling pretty rough, and seems to be rich . Fuel actually misting out the top of the tbi.
Any ideas?

 

how long did u let it run after the change?....you prolly have to much fuel in the intake..(flooded sorta speak) give it time to burn it out..for bit..

check your plug wires..make sure you got the correct firing order..1 plug off gonna run like sheet!!!!!

 

So now I have determined I am losing 12 volts to fuel pump and losing the 5 volts to throttle position sensor.
Is it the computer?

 

Usually this is caused by reversion in the intake (combustion pressure going backwards) which in turn is usually caused by a valve problem.

No neither of those things "is the computer". More likely, a bad connection somewhere. If your car has the in-line fuse thing off the battery (can't recall offhand which ones are wired that way) then that's where I'd start looking.

 

That's my thought too. Here's your wiring diagrams
http://austinthirdgen.org/mkportal/m...ine_wiring.gif
http://austinthirdgen.org/mkportal/m..._continued.gif
http://austinthirdgen.org/mkportal/m...ody_wiring.gif

 

Thank you , I will start looking deeper.
Thank you for the diagrams