I have a 1985 Nissan 720. Z24 engine with 170k.
I bought it earlier this year and it ran fine up until a couple of weeks ago. It idles fine, and when not in gear I can rev it up and there are no issues.
However when in gear I can get rolling fine but when I start approaching the higher band of a gear ( all gears ) the engine starts to lose power and it sounds like it is choking it self. This has made it almost impossible to drive at highway speed or get enough speed to change to a higher gear. At the very least it makes for very poor acceleration.
I have changed the fuel filter, and the old one showed no signs of dirt or debris collecting inside. The engine was fine before, with lots of power and doesn’t burn oil.
I had some work done to the vehicle and it started after that, but it doesn’t seem related as they were ball joints on the right side and leafspring bushings.
Any help would be appreciated as I am off in the sticks and worried about being able to get out of here.