Car in question is my Mom's '92 Spirit with the 2.5, has 90K miles on it.

With no rhyme or reason, the car will momentarily surge then loose power while at speed (usually 50 or faster). It never completly stalls, just looses RPM's. Working the gas, the car will kinda 'jump' then sputter a few times, then 'catch' and act as if nothing happened. Around town, 40 or slower, the problem never shows.

This happened once before about 6 months ago. With the way the car acted by working the gas, I just put a TPS on it. Car ran much better afterward, even better than before the problem showed up. Car has run fine until today.

Could it be a bad TPS? Yeah, I threw on a 'house brand' last time. Has it come back to bite me in the rear?

Would a bad TPS set off the check engine light? Its not on and didn't come on last time either.

Anything else I should look at?

Thanks.