1978 grand prix

[Williep]

Bought recently and starting to update things. Driving to the coast yesterday, at about 70 mph, hte car started to bog down- took foot off gas and then back on and all is good- get back to around 70 and happens again. Had been on highway for 2 hours with no issues. Did again today-
also the trans. If you baby it, all runs great. If you get rowdie, it will not get out of second until you stop and then baby it again and then it shifts through all gears - you can downshift and then put back into 3 rd and all is good

any thoughts or suggestions -

 

[jcelk]

cheak vacuum to trans module cracks in it or just old rubber hose will give you problems . it;s a good idea to just replace the rubber hoses by the trans and by the intake manifold best of luck