Technically this post might not really belong in this forum, because it concerns a 1986 Trans Am...but since camaros and firebirds are practically clones I thought I'd try here since the firebird forums I've foundaren't quite as active.

1986 Trans Am, 4 bbl 5.0L manual

The car usually runs without a problem; today my brother was out driving it and suddenly the tach and speed gauges started jumping up and down and the engine started running really rough. He pulled over, shut it off, and couldn't get it started. Here's the strange part: the dome lights worked, the alarm worked, but none of the usual gauge lights (back lights, check engine light, etc) lit up when the key was turned into the on position. In fact, if the dome light hadn't been on, you would have thought the battery was disconnected. The engine wouldn't crank.

We disconnected the battery, poked around under the hood, didn't find anything strange, reconnected the battery, and the car started up (although it was a very roughstart)and drove almost perfectly the rest of the way home.


Any ideas?

 

did you hit any potholes before it acted up?

 

The alternator may be going on you. The battery is suppling most of the juice and soon it may go. Don't plan any long trips and have a towing company phone number with you, because it is just a matter of time.

 

When I hear alarm that is always my first concern. Was the alarm wired into the ignition to kill it? Was it also wired in to where it would flash the lights that were not working? What is strange is why did the speedo jump. Maybe Firebirds went to electric speedos earlier. If it was cable it should only be affected by the speed of the car.

 

Well, the problem seems to be intermittent. I doubt it has anything to do with the alarm since when the car is acting up the alarm still works. The alternator voltage seemed alright when I tested it. What's interesting is the rear parking lights, as well as the hazards, begin to blink rapidly when the car starts to choke. The enginegets really rough and the car just about wants to die. I suspect somewhere there's a ground problem.

 

did u happen to drive in alot of rain recently?
because i have had something like that happen to me but it was in a 97 buick.
and it was cuz i was driving in alot of rain and im guessin the altnator got a bit to wet and shorted out cuz i replaced it and it ran just fine.
all though this is a newer car with more electronics. but i would prolly say its the altantor.

 

This wasnt a Firebird or Camaro but I had an 85 and there was a box under the hood that a lot of the electrical equipment all connected to and there was one plug in that box that if it came unplugged NOTHING would work... it acted like the battery was gone. I dont know about your car but I would look for somthing like that. Good Luck

 

does it fart and gag???in other words missfire, pop back through the intake????? and what do you have for fuel pressure. check the ground by the tank they sometimes break and give you trouble

 

In case anyone was keeping track it was a simple wire contact problem. The wires leading to the starter solenoid were completely corroded. One of them slipped off froma light tug (out of the connector), and the bolt holding them down was lose.We replaced the wires about a week ago and haven't had a problem since.

As usual, thanks for the feedback.