Truck starts and idles fine but boggles down when put under a load. on 1997 Dodge Ram 1500

I have replaced the plugs, distributor cap, rotor. check the thtrottle body sensor and the volteage did not increase when the throttle was moved so I replaced the throttle body sensor. Checked it and the voltage increased and the trottle was increased. Thought I had the problem solved but after a test drive it still has loss of power. took off the throttle body and cleaned it as well as the IAC and also checked the map sensor to make sure it was not clogged. Truck still has a loss of power and the idle now is slightly higher. I would also note that the check engine light is not on. Any advise. Thank you

by in Kimberling City, MO on January 20, 2014
2 answers 4 comments
ANSWER by on January 20, 2014
What is fuel pressure? Is the exhaust plugged?
COMMENT by on January 20, 2014
I have now check the fuel pressure and it is consistent around 52 psi. Checked it again and is was 35. RE checked went to 52 and the needle is now bouncing severely
ANSWER by on January 20, 2014
REMOVE AN O2 SENSOR AND DRIVE TO SEE IF ISSUE IS GONE,IF SO EXH IS PLUGGED
COMMENT by on January 20, 2014
I will try that thank you. I removed the upstream o2 sensor and it made no difference it still bogges down and has no power. I also unhooked the MAP sensor and the truck still started. ???
COMMENT by on January 28, 2014
Bad pump
COMMENT by on January 28, 2014
I believe so and have ordered a new one. Hope to put it in tomorrow. Thanks for all the help