Loss of power,sounds like it is sucking air in threw the exhaust. .need help

 

Welcome to the forum

Not much to go on

4.0l SOHC is the engine you have in a 2001 Ranger

These have known timing chain issues 1997 to 2003
So could have skipped time, i.e. sucking air thru exhaust................
Try compression test on at least one cylinder on each bank, it can slip time on just one bank/side of the engine
It runs 9.7:1 ratio so expected would be 170+ PSI

Could be blocked exhaust as well

 

Thanks Ron d ...my truck has done this before and it straightened back up after I kept on trying to drive it (I'm poor lol)so I thought it was bad gas I had got before ....it's not straightening up this time though hopefully it's not too expensive... going to cut off catalytic converter and see if that helps ... crossed fingers