Now I have had a chance to put a few miles on the Vista a problem has reared its head. When it warms up I seem to lose power. When I try to
Pull away from a stop light or junction there seems to be no power there st all. Also hills are also entertaining. It doesn't seem to matter where I have the throttle it makes no difference. It will after a while pick back up and then build speed up again. I still feel then that it should have more oommph than it has. Another, maybe related issue, after a long ish run if you remove the fuel cap there is a big hiss of air and its sounds like fuel bubbling. I'm going to do obvious and check vac lines etc tomorrow but wondered if anyone had an advice.

 

Does a Vista use an SP Jetaway? If it does check the operation because if the torque converter is not changing it could be a real dog. If the Vista is the same as the Cutlass of that year the gas cap is not vented. Is the tank building pressure or vacuum?

 

Leave the cap loose and drive it, the tank or the cap has to vent to allow fuel flow. Air fills space when the gas is used up.

 

Tried it with the cap loose on the way home and was still down on power , tightened it on way home and still down on power but when I released the cap there was a rush of air and could hear fuel bubbling