hcompton, there is nothing wrong with TPI, it was a great setup for its time & it still works perfectly fine for a lot of people now, myself included.
a better TPI intake for high horse power/high RPM is NOT anywhere near $5000.00.
no need for a throttle body if you get the right TPI intake.
replacement injector are NOT $400.00 for a full set.
NO system will last for 30 years without repairs, carb or FI.
newer vehicles have many more wiring problems than the older vehicles did at the same time or mileage, and those problems will only increase as the late model vehicles get older.
repairing or replacing a wiring harness isn't a big deal if you know what your doing.
chphlds, i did a quick read thru of your other threads and i'll be repeating some things.
the painless wiring harnesses are pretty good quality, at least everyone i've seen has been.
from the ECM number, your system is a MAP system.
using the MAP TPI system is very popular for swaps into hotrods as it allows for a much cleaner install vs the MAF systems.
the cold start valve, or 9th injector is not needed with MAP.
with a painless harness, you should have the ALDL connector & SES light, find the connector & the light. the light is probably just an orange light mounted next to the ALDL.
if the knock sensor is not programed out of the ECM chip, the ECM will have a code for it & the CEL will be on all the time and the motor will have reduced performance.
the light should come on at key on. if the light works, jumper the ALDL terminals A&B & turn the key to the on postion. the light should flash out any codes. with no problems it should flash code 12. if there are problems, the code 12 will be followed any other stored codes.
its not unusual for the knock sensor to be programed out for an install like you have.
a call to painless wiring may turn up some good info about things such as what the base timing should be & how to check it.
with it running fine once warmed up, it sounds to me like it is going into closed loop & the ECM is controlling fuel.
what is the fuel pressure with it running at idle?
i can't tell from the pictures, but being an aftermarket install you may have an adjustable fuel pressure regulator.
a data log from the ECM could go a long way.
if you have a laptop, you can build or buy the ALDL cable, download the software & do some data logging. TunerPro is a great little program for data logging. using TunerPro with a laptop you get a much longer data log & the update rate is faster than what any of the scanners do.
something i see in one of the pics and don't like, what do you have for a crankcase breather filter? please tell us it does not have a second PCV valve on the other valve cover.
are you on the thirdgen site?
not taking anything away from Hotrodders, but thirdgen truly is the premiere site for TPI systems.