give it gas, rpms dont go anywhere

[2gredspyder]

ok im not sure if u guys could help me with this because its not about my talon. its a 99 diamante that my brother in law owns. the car has been sitting there for a while and today we went outise to start the car, it started fine but when u give it gas, the car wont accelerate. i cheked the tb and its not stuck. we kept trying and then it accelerated but than it stoped working again and it wont accelerate. any help would be appreciated

 

[Defiant]

Clutch if a manual, gearbox or trans fluid if automatic.

 

[2gredspyder]

its an automatic, but i dont think it has to do with the tranny. the revs wont move even with the car in park or in neutral. im thinking that it has ignition problems or something wrong the the tb