Trouble with 92 Sentra E acceleration

I have a 1992 Sentra E with 133,000 miles. It's a 4-speed manual with all original equipment.

I'm finding it's not accelerating the way it used to. For instance: when I reach speeds of 60 mph or higher, I have to rev the engine very high to get it faster. It's almost as if it's slipping somehow.

Is this a transmission or engine problem? Or something with fuel delivery?

Thanks.

it's probably your clutch. if u hear the engine overrevving and you're not going anywhere then it's definatly your clutch. since you have an e
i doubt you have a tach cause if u did u would see the revs climb and your speed stay the same or even drop

I think you may be right. Turns out a few other folks agree with that too. Makes sense. Engine seems to be working just right and after doing a little checking yesterday, is still pretty smooth.

I'll see what the mechanic says. Clutch is out of my league.

And no, I don't have a tach since it's just an "E" model. Being an old VW person, I learned how to "feel" the car rather than rely on a tach. She hasn't done me wrong until now.

I'm just hoping the clutch cable is out of adjustment and that it's not oil on the clutch.

Thanks for your help,
Tony P.