i did a half assed search and didnt see anyone with my exact problem. im postin under this topic cause i was told its more than likely a problem with my ecm so heres my story. im driving down the road when suddenly my car wont accelerate and begins to rev up and down up and down all on its own. i give it gas but that changed nothing. the car is jerkin but only cause its still in drive so i shift to neutral and roll to a stop and turn it off. i wait a few minutes then start her up still kept revin up and down for about 5 seconds then died. i tried that two more times while lookin under the hood just to see if something is outta place and before it died for the last time smoke startin comin out from under by the headlights on both sides. waited bout a week before i tried to start again and it didnt even turn over. but i think my battery is dead it doesnt look like its been changed since birth.

im tryin to do it myself to save money cause my nissan needed a new computer and burned a 800 dollar hole in my pocket. help will be deeply appreciated =)

oh yea its a 1991 Z28 350 TPI

 

I'm having a similar issue, to add a little to yours.

While driving down 121 my cars battery began to drain, i was initially cruising in 5th gear and the rpm meter began to sputter (which it doesn't work in the first place so that was weird) and i couldn't accelerate. So i dropped down to 4th gear and the same problem happened again and again until i was riding on a highway in 1st gear.

Battery finally drained all the way out after a couple of backfires and power steering went out so i had to leave it.

I'm hoping replacing the ECM will be the solution.
But would want to have a second opinion before ordering parts.

 

Had the same issue, took 3 batteries to get home from a long trip, even after I installed a new alternator. I took it to a local mechanic, he rewired my cooling fan relay (Basically bypassed the relay). Now I can drive under normal conditions and get a charge; however, when I run my A/C my battery still drains like before. Also, my cooling fans no longer work. I un-f*$@ed the wiring hack they did, but still no fans. I've troubleshot everything I can think of and everything checks out fine. I get power where I'm supposed to and grounds where needed. The only thing that doesn't check is a code 15 "Check ECM connections". The ECM is my last "fix", and the only thing I haven't tried. I've replaced almost every sensor or relay on the car and it still acts up, stalling/sputtering and not wanting to start back up. I'll let you guys know how it goes. Should get it in within the next few days.

 

Hate to tell you, but the ECM didn't fix my issue. Also replaced the coolant fan switch on passenger side cyl head to no avail...

 

I should of asked sooner when I had problems, but take out the ECM, open it and inspect it close, if the board has any burnt spots, you can track down whats shorting out that way.

 

it was my distributor... replaced cap, module, and rotor

problem sloved