My 94 beretta v6 3.1L will start every time, but after it warms up it starts to run rough and hesitates and seems to have a loss of power. It acts like a bad fuel filter or clogged injectors, but I replaced the fuel filter and ran fuel system cleaner through it and the problem still persists. It is most noticeable when idling and when running around 60-70mph and when accelerating. Any suggestions?

 

A better description may be that it chugs when kept around a steady speed and a little when accelerating and when at idle. That is what I'm trying to figure out and fix.

 

Is there a check engine light?

 

there was a check engine light that would come on sporadically until I replaced the throttle position sensor today. Now the engine light doesn't come on but the original problem still exists.