I turn the key to my rebuilt '87 350 TPI and it fires right up when cold. I warm it up about 5 min. then turn it off. I turn the key, starter cranks and cranks but no start. I wait 5-10 min. depending on how cold it is outside, and she fires right up again. REALLY WEIRD PART: When still hot, I hit the remote starter button hooked up to the "s" starter relay and to the battery and she fires right up....turn off, put key to on and hit the remote starter button, fires right up. Turn off with key, then turn key to crank, starter turns but nothing happens!!!!! I did a complete rebuild when doing an engine swap. New rebuild on distrib. cap including coil, ignition module, etc, but as I finished project, i had trouble with wiring and bought a new wiring harness and computer and the engine finally started for the 1st time. New fuel pump, new injectors...Runs great and idles awesome, never dies or stalls, just this hot start issue...should I spend the time and take off the cap and have it all tested inside even though it is new? Why will it start by the remote starter when warm but not the key, only turn over and over. Checked fire, perfect, sprayed starter fluid in the intake as someone was turning the key, nothing!! Push the remote starter button, varooom !!!!!!!!!!????????????????????
Help please!!!

 

I am having the same problem with my 91 RS 305 TBI. It doesn't have the auto start, but if it is warm and then I shut it off it won't start back up. Just crank and crank. Wait for it to cool down, then it will fire right back up.

 

.. Spark at plugs with remote starter button... but NO spark at plugs using key start.. correct?

 

HOCKINJM and all others interested:
I figured out what the problem was with my Third gen TPI 5.7L:
The ignition wire to the computer was not hot while cranking. I did a 5.7 TPI conversion into '87 FJ60 Lancrusier. Every thing was wired from scratch using parts off the old donor corvette wiring harnss and alot of nice new wire with shrink wrap and all. The engine would turn over but not start. Thought it was ecm so I purchased a new one....still same problemo! sometimes it would fire up when it was cold but then not start if I turned it off after 5min... I finally gave up after a year of trouble shooting and trying to get this baby wired correctly...Finally I broke down and purchsed a professional wiring harness with all new connectors and fuse box. I tore out almost everything I had done in over a year and istalled the brand new plug and play wiring harness. Looks really tight..BUT: same symptoms... I thought maybe grounds, so I did way overkill of tight grounds...engine to firewall, frame, and Battery, all fat wire sodered to copper lugs...STILL same old stuff.... Couldn't figure it out, but when she did fire up when cold, i would drive around and fine tune, etc. When I stopped somewhere I would park on hills to roll start it when it was hot and this way I kept trouble shooting to NO AVAIL!! One day I was at my buddy chuck's house and he started running around with the test lite. While I cranked, he went around with the test lite...He found the there was no power going to ecm while cranking the engie. I some how picked a ignition hot wire that does what my stereo igition power wire does: On ACC the stereo goes on but while cranking the engine, the stereo goes off, then the engine starts and the radio goes back on. I can't believe out of all the live ignition wires under the dash, I picked this strange ignition power wire and I never even thought to check this computer ignition wire while cranking..I now lookback and bells should have been ringing just by chance I thought I'd try bump starting it. Everytime I would roll/bump start it, it would fire right up! This is because the ecm had power as I would bumpstart without the starter cranking. Alot of lessons learned overthis project!!!! now that I got this rig on the road, it is amazing. I get 16MPG on the highway with 35 inch tires... better than stock/original carb. engine- weighing in at over 500 lbs with stock size tires! I dropped almost half the weight with this tpi swap. Oh boy does this jewel of a truck get up and rock and roll! I can be cruising and be getting 16 MPG, then I step on it moves like a mad dog but it also jumps down to 5 MPG in miliseconds at WOT!! Very fun to drive but Trying not to scrach the tires in second gear...not nice to my running gear! If I was to do another engine swap, I would choose the 5.0L TPI like yours...i would be pleanty of power, Im sure, and a little better MPG tooooo! More lessons learned...
Did you figure out your problem? If you haven't figured your problem out, try a new gas cap. They are cheap. With a bad cap, vapor locks can create problems... Had a couple of old timer's tell me this...Didn't work in my electrical problem case...
Happy holidays and GOOD LUCK!! will try to post some pic's of this swap, looks impressive and even though it went into a toyota, it is still looks amazing and has mucho performance.