1999 Chevy Malibu Lights flashing before jumps between gear

could be about anything. have you had the vehicle scanned lately

I've taken it in twice and first they said it was a detached vacuum line....they reattached it and problem is still there...still lights flashing and car jumping. Then they said the battery was not holding enough voltage and maybe that was affecting the fuel injectors....so they replaced it and still same problem.

sounds like you might be having a computer problem. Or a power or gound with high resistance somewhere. Especially when you start talking about the headlights being dim. It also could be a alternator. Take your car somewhere and have them check the alternator. even the belt. If good. Then i would recommend telling the shop to check the powers and grounds to your computer systems.

i agree have the alternator checked, but i would also have the PCM scanned. I have never seen a alternator make a transmission act up. Thats why i think there is more to it than just a alternaor.

yeah, ive never seen the alternator do anything to the transmission but if you start missing power to the computer systems on the vehicles now, it will definately make stuff act weird. Also, i see alot of problems that come in to the shop where scanning the Powertrain Control Module doesn't even help. Or any of the computers on the vehicles. I would check connections at the computer looking for water intrusion of some sort.

thanks for the advice. Another thing that just started happening is the battery light comes on....this rarely happens but does.....and it's new. Also the air conditioning comes in and out...which I forgot to mention

If it's the PCM....does that mean big money to fix? Does anyone know where the PCM is located in a 99 chevy malibu?

have the voltage output on the alternator checked and get back to me. you can check this with a volt meter. should be 13.8-14.5 volts. Your AC might be low on freon if it is cycling in and out. you will have to have the pressures checked.

It should be below the left side of the Instrument Panel close to the steering column.

I took the car in and they said it needs a new alternator and a new transmission.....in other words.....take it home and let it die. THey said there is a tube that is full of metal so it's only a matter of time before the transmission goes. I don't understand why the transmission only acted up when the lights were flashing....if it has it's own problems I would think it'd act up without alternator symptoms....maybe they just were saying it's not worth fixing the alternator when the transmission is almost shot. thanks for all of the advice.

i would say if you really think it is the alternator, just put one in and see for your self. if it doesnt fix it return it.