My 89 GT has lost power while accelerating and I've been trying to figure out why for quite a while. I don't know a whole lot about cars but I'm learning as I go because this mustang seems to have a lot of problems.

I just remembered seeing something that looked like a spark plug with a wire coming from it attached to my exhaust while I was under my car a week ago. I just found out now while searching online that the "spark plug" is an o2 sensor. On the driver's side exhaust the o2 sensor was attached to a plug. But on the passenger exhaust the wire of the o2 sensor was cut; the wire was just hanging there. Could this be causing the car to have low power while accelerating?

The car has an offroad H pipe with no cats.
Thanks in advance for any help.

 

It could very well be that. My car isnt running up to 100% either. If you replace those 02 sensors let me know if it fixes your problem

 

Those o2's are there for a reason. You should get that fixed, mid as well do both while your in there. May not cure 100% of your car's performance issues, but it can help.