84 Trans Am randomly loses power and dies

engines

#1

O.k. here’s a little about the car before I start about the problem because my car is very custom. It is a 84 pontiac trans am with 305 H.O. code G engine V8. It was completely redone about three years ago and runs great. We did delete most of the computer control stuff and emissions. We now have a vacuum controlled distributor instead of the original computer controlled one. There is no engine light to check now and here’s why. We have converted the car into K.I.T.T. from Knight Rider, so the entire gauges on the dash have been turned into digital gauges including the speedometer. The new gauges run off of the same power that the old ones did. But we have added a separate switch to turn just the dash on for car shows so we don’t have to turn the key on. it goes to the fuse for the computer/ gauges and a few other little things. We also have two lcd screens installed and a computer.

Now for my problem. The car still runs great no issues with how it runs or sounds engine wise. It doesn’t matter if it is cold,hot, wet, or dry. I can go down the road and all of the sudden all the power to the dash will flicker off and on. I usually lose my speedometer then and don’t know how fast I’m going. It will not power up fully unless the car is started normal. The car has to have the gas pumped a few times before starting normal. No biggie.
Now, the entire dash will flicker and sometimes when it goes out in the middle of driving, the car just dies. About a week ago everything lost power. No headlights, flashers, interior lights or power to start the car. After a few minutes, one by one the things starting to work. Interior lights first, then headlights and five minutes later the dash lights come back and the ignition has power again.
Went to town the other day and drove for an hour and no issues at all. Today, the lights flashed on the dash, get home, shut the car, turn it back on and fine. Waited a while and had the door open. Shut the car off and it lost power to the ignition. Interior lights were on but no power when you turned the key. The radio would flicker on/off real quick, but no power to the dash or to start the car. Turn the key to acc mode and the radio works but again no power in the on position to start the car or turn on the dash.
Now, we can turn on the extra switch to power the dash and it will come on but not when I turn the key.About ten minutes later of just sitting and the car was back to normal. Turn the key and power was back and started right up.

Here’s what I’ve done. Battery and alternator checked out fine, checked all ground cables to firewall, starter, etc, looked for lose wires or melted wires, took distributor cap off and check that area, clean battery cables wires, looked for any corroded or dirty wires, made sure all wires were tight. I even went under the dash and put in a new ignition switch ( I don’t ever want to do that again. That was a pain in the neck and I really mean in the neck) Still the same issue.
It seems like something is getting hot and causing power to be shut off to the ignition and keeping power from getting to the ignition/dash until it cools off. Anyone have any clues that I might have missed? Sorry for this being so long. I just wanted to make sure I put all the info up on what is was doing and what I’ve done to check it. I hate these kind of issues because it is so hard to track down. Thanks for any help.


#2

tried to replicate the issue with no luck. Ran the car for about 30 minutes, turned everything off and on, pulled panels and wiggled wires around on everything I could find, even on the starter as it was running, moved it in the driveway but to no avail. It seems very random when it wants to do this issue. I thought maybe heat but it is very hot outside and I ran the car with it constantly having the fan come on to cool it off and no luck causing it to do the same issue.