93 beretta stalling, help!

[bettinabeck]

hi, i have a 93 beretta, 3.1l v6 automatic and about a month ago my it started dying when i let off the gas, but it didn't happen all the time. but now whenever it's not in park or neutral it starts surging and just stalls when i let off the gas. it surges in reverse the most.
the SES light has not come on, but i scanned the codes anyway, i got codes for the TPS ( low voltage) and the MAP sensor (low voltage). i replaced those parts along with the o2 sensor, the ICM, the thermostat, and the crankshaft positioning sensor. but it's stalling out, now even more. i scanned the codes again and still got the TPS and MAP sensor codes.
i've been told it's the tcc solenoid and i'm working on getting that fixed.

anyone have any ideas on what it could be? my mechanic friends and i are all out of ideas & i just don't want to get rid of my car!

any help is much appreciated!

[3X00-Modified]

For the mean time you can just unplug the TCC plug from the trans to see if that fixes it, but usually that will only cause it to stall when coming to a stop, unless the solenoid is stuck. Reset your codes to make sure the TPS and MAP ones are gone and its not running in limp mode somehow. If they come back then I would suggest having someone datalog it with a tool to see what those sensors are reading to possibly diagnose a wiring issue.

And double check to be sure they were stored codes and not active... I say that because your bulb may be out for the SES light. Turn the key to the on position and don't start it, the SES light should be illuminated, if not the bulb is bad and you may have a wiring fault on those two sensors and thats why the codes are still there.

[bettinabeck]

my tcc was unplugged when i bought the car, but one of my friends plugged it back in & it ran fine for a few thousand miles.
but i recently unplugged it & it didn't solve any issues.
about the codes, the first time i checked them i only got the MAP sensor code. so i replaced it.
but when the car kept stalling on me i checked for codes again and got the TPS and the MAP sensor again.
so i replaced the TPS, reset the codes and i'm still getting those two codes.
and my SES light does work.

Also, it's been idling at 500-700 rpms, is that normal?

[bettinabeck]

i forgot, i've also replaced the front head, plugs and wires, battery, all gaskets except the exhaust manifold gasket, and the pcv valve.

[scd88ga]

This could be another case of the "Faulty EPROM"!

[3X00-Modified]

Yeah it sounds like either a wiring disconnect somewhere or the prom is on its way out, especially if its "throwing a code" but not illuminating the light, those are both light illuminating worthy.

[wi_corsica]

Does it just stall or does the RPM go up and down at idle?? I had a dirty throttle body that got so bad the car would die on me.

[bettinabeck]

i definitely think it's an electrical issue, but i'm sick of guessing at it. me & my brother decided we're going to have a shop diagnose my car & go from there because this is just nerve wracking!

@wi_corsica - when i replaced the head i cleaned out the throttle body & all that good stuff.