91 t-bird runs fine but sometimes losess all power...

Check catalytic converter.

Possible short in brake light switch.
Possible bad alternator. Check voltage at battery when running.

Should be 12.7-13.8 V.

Generally speaking, if the starter was dead it would not jump start.
Sounds like the key switch or the neutral safety switch.
You would need to know if the starter has power when the key is in the start position.

It could be the vacuum modulator on your auto transmission, sometimes when vacuum hoses fail,split or whatever, they can suck up impurities causing other downstream items to fail. Also check mechanical linkage form shifter in cabin to transmission gear selector arm. If jumps were happening these might have worked loose. Best of luck!

i have a 91 nissan max...it starts but it wont get the gears when i put it on drive it want to get it but doesnt run!..what can i do?help?asap

2nd gear is the fail safe gear, that car will run in second if there is a transmission problem to get you to your local repair shop, sound like you need a transmission you can check the fluid level and try adding a product called LUCAS transmission conditioner to try and help revitalize your transmission, sometimes this works.

sounds like the connecting rod to the drivers side is broken loose from mount, can try to reconnect rod, actuator on passengers side is not working possibly mmm i think those were vacuum line run so check vacuum tube. If mount is broken possible epoxy together. both fixes shouldn't be too bad and correct running lights, a Chilton or Hayes repair manual would help you with diagrams and instructions, and any of the fire bird forums would be able to give you more help. Good luck on fixing up that old bird, hope you have a v-8.

check your contact points are set correctly, or may even be burned , if so replace them , its a comon thing if the contact points are badly set ,when you put the car in gear it will stall or wont idle , i had a 67 t/bird landau that did exactly the same , , turning off the highway was a night mare ,i had to keep the accelerator pressed while i braked , otherwise it would stop and then i would have no steering ,very annoying and very dangerous

pull off the transmission transition switch wire pluged on to tranny
start car drive should be fine never hook op again 0 money
or pay 700 dollars to install a new one
or buy switch pull tranny and install your self

my 92 t-bird would stall found out it was the brain 250.00 part & labor