BigP

I've got a 98 Trans Am. Something weird happened while driving the car this morning. I was doing about 50 MPH and the airbag light came on. It flashed then went out. About 4 seconds later I hit the brakes, the check gauges light came on, and all the instrument cluster lights lit up. The gauges went full tilt boogie ie tach was at 7000 RPM, speedo at 155 MPH and the oil, coolant temp, and fuel gauges pegged. The motor shut off and I lost power steering and brakes while other cars on the parkway are barreling towards me at 70 MPH. I got it pulled over to the side of the road where I cycled the key, started the car, and had no problems since then. Took it to Pontiac on my lunch hour so they could hook up the Tech 2 to it and they got absolutely no codes at all. Just cusious to see if anyone else has had this problem or if it's just me. Thanks in advance to any replies to this post. Thanks again, Paul Moore

jimmy 2 Times

iTrader: (18)

i had that problem when the dealer broke one of my alternator wires, the car just died, and smelled like rotten eggs, took it back to dealer, fixed the wire, and i was on my way
dont know if yours is the same but worth a shot
jimmy

TA TED

Battery or battery connections. A high resistance connection can cause intermittent operation of the guage cluster.

FourthGenSS

The battery/alternator options sound like the best bet to check first. Another possibility that you don't want to hear is the computer. I had a cavalier commuter car that did something simmilar. In these cars the computer controls everything. There is one for the cluster also. All data for the speedo and tack are serial data from the computer, engine management and everything is controlled by it.

jimmyblue

iTrader: (11)

Check the battery and alternator connections, but
do not forget the other side - the ground returns.
There are braided ground straps from the engine to
chassis that can get loose or get damaged in work
and lose you the current path that the electrics-
heavy motor needs to stay tight with the PCM
and the chassis electronics.

Many sensors / actuators are "fed" from chassis sources
but returned first to engine block ground. An intermittent
ground fault can make them all jump up to 12V and freak
the computer, then get all better when you cycle power
and reset things.

cablebandit

iTrader: (37)

make sure you don't have an aftermarket add on power wire slightly grounding. mine did this when my dual fuel pump wire was grounding atiny amount. Of course I didn't figure it out until it grounded big time and burnt up the wire...I shoulda fused it!

Cheatin' Chad

iTrader: (3)

I'm having this problem. replacing the alternator and battery has not helped.

after doing a few searches it appears this happens mostly w/98's.

Anyone know the differences in charging systems between the years? If there is a difference the information could help track down the problem.

thanks

Snootch

iTrader: (3)

One connection you might want to check is the battery/fusebox connection... There is a wire that goes from the battery, runs just behind the fans, and attaches to the underhood fuse box. The connection point has a red plastic cap on it. That connector got all nasty, and heated up to the point where the brass post on the plastic box actually softened up the plastic, and sunk slightly deeper, causing an intermittent connection. I took the cable off, and got a brass washer to make a better connection after I had cleaned the connectors up. Before I fixed it, it would get so hot that it would immediately boil a drop of water on the connection. Once I repaired it, it cooled down considerably, and my voltage went up slightly.

Cheatin' Chad

iTrader: (3)

Checked it. It looks fine. Anything else?