Hissing loss of power only when accelerating

Hey guys. Sorry didn’t want to have to post a new thread but am tearing my hair out with my issue.

I have a 96 Tacoma 2.7. Truck starts and idles completely fine and accelerates good when cool. But as soon as it warms up I get a loud hissing noise when accelerating from engine bay and engine is limited to about 2k rpm. Strange part is it happens intermittently. I can let off the gas and try accelerating again and it sometimes will accelerate normally.
Any help would be much appreciated. thanks

 

Check your exhaust manifold for a leak.

 

strong possibility that your catalytic convertor(s) have fallen apart and intermittently plugging the exhaust. Step 1, bang on the convertor(s) and listen, does it sound like things are loose inside? Step 2, If possible loosen the exhaust manifold to exhaust pipe and take her for a ride and see if it is fixed. There is also a possibility that some of the broken pieces could be caught in the muffler with the same effect. A muffler shop can test back pressure... they used to do if for free.