I have an '88 firebird that originally had a 305 tbi, now it has a 350 tbi. Yesterday, I was driving, listening to the radio when I noticed that the song was skipping. I soon noticed that my radio was shutting off, then immeaditly back on. It progressed worse into the day, I noticed the gauges were flickering and the needles moving around a bit. Then it just shut off on me when I was turning onto my street. Started right back up. Today it shut off on me twice while I was driving. Although it didn't sputter and stall out. I saw the gauges go down, then the engine just shut off, like my alternator was bad and my battery just ran out of power. But no, it started back up. I noticed after that, if I saw the gauges moving, I could stomp the gas and it would keep running.

So I'm lost here. I think tomorrow I'm going to rip the alarms out and see if that makes a difference, I've been planning to do that for months now anyway. (It has a newer cheap alarm as well as a security chip from the 80's, like a VATS but not on a key, about 1 1/2" x 1 1/2" that you put into a slot below the OBDI port.)

I thought about it being the ECM too, but I'm not sure on that.

 

Check the ignition switch for burnt contacts/terminals or possibly a bad connection with an aftermarket alarm system. Sounds like an ignition power problem.

 

also how old is the battery, it could be throwing a spike.

 

check the battery connections and ground wires..

 

I was just about to post the same problem when I saw your thread. I have a 86 2.8. Its happened 3 times to me over 4 months. First 2 times it was just like the power skipped for 1/2 a second, the gauges when down the head lights blinked.

But yesterday when I was driving on a busy street it happened and killed the engine and even erased my radios memory. My battery is just over a year old and mine doesn't have an alarm.

 

So I finished pulling the alarms today, drove it a short distance, shut off on me 3 times, once when I was pulling into my driveway. Only now it barely wants to run, I'm thinking it's the ignition coil now.

 

I had the same problem happen to me last year. My alternator had gone south and was running off the battery. I replaced the batt and alt and never had the problem again.

 

On my anyway, the alternator is charging good and the battery is pretty new so I don't think thats the issue.

 

First you should clean all your ground connctions. Remember that current flows from Negative to positive. If your grounds are corroded or loose they will cause crazy stuff to happen with your electronics to include your ECU. To check the alternator just check the battery voltage with the engine running. With a volt meter read across the battery post and they should read 13.5 to 13.8 volts. If you read less than 13 volts your alternator is going south(bad).

 

Look at the fusible links down by the starter solenoid, I had these pop on me while I was driving down the freeway going 70 mph. The gauges all pegged and and it was if someone had to turn the key on and off really fast, then the car died.

 

so my ignition coil tested bad, I replaced it today. Then I drove the car. At first it ran a lot better, but then it started shutting off again. So I'm back to where I was before. I'll be checking the alternator in the morning as well as everything else I can think of that may be causing the problem.

 

I recently put in a battery disconnect switch and my car started doing the same thing... I would go to slow down at a light and it would shut off... Its a stick shift, if I kept giving it slight rev's, it would be ok, other wise... Off... I removed the battery cut off switch and no more problems.... so I would also try / test the cables / grounds / connections...

 

So I took the battery out and I saw that the wires going to the alternator were badly corroded. So much in fact, that when I took the electrical tape off, they fell apart. I replaced the wires with new fusible links, no more problems!

 

Glad you got it fixed before it got serious.