So i just purchased this 85 IROC only has 25,000. She sat for 4 years before i got her. The 305TPI seems to be running funny. We have replaced the normal tuneup stuff. ie plugs, wires, fuel filter. all that did help. now for the weird. when driving her at night she bogs down around 4,000 and doesn't want to shift.(auto) the car does the same during the day but it is worse at night. The mechanic that was looking at it just wants to keep replacing parts to "test". So i figured i would ask here and see what you guys thought in advance.