1998 2500 7.4 lacks power

[jjs1234]

I have changed the fuel filter, the rail pressue to the Injectors is 53, with the key turned to the aux position, at idle it is at about the same.Hit the gas hard and it takes a quick dip and recovers. The truck idle's file , when you put your foot in to climb a hill is bucks and lacks power, I have to drop it out of overdrive and use (3), my Deisel Golf can take it on the hills (at 90HP). I have checked the air filter, do the injectors have a history of problems on this engine? Once and a while it acts like a 454, any suggestions?
The engine has 98K

[amac209]

fuel pressure should go up when you hit the gas. i'd be looking at the regulator. check all the sensors with a scan tool as well. a bad tps or O2 sensor can cause problems also stuck egr or plugged exhaust.

[pickering_c]

There are now about 5 of us here with the same problems out of our big blocks...

I ran mine through a decent OBD2 analyzer. I have dual cat's and 4 O2 sensors. It is running extremely rich out of the back O2 sensor on the #1 side (I would have to assume that would be the drivers side). To compound the problem, the #1 side is adding extra fuel at the injector (long term fuel trim). That seems to explain why my mileage had dropped off.
We are going to start swapping O2 sensors around to see if the problem follows the O2 sensor; starting with the rear ones. The bummer of the whole deal is that it is a one tyr per day project because of the heat under the cats.

[rrzimmer]

Originally Posted by pickering_c

There are now about 5 of us here with the same problems out of our big blocks...

I ran mine through a decent OBD2 analyzer. I have dual cat's and 4 O2 sensors. It is running extremely rich out of the back O2 sensor on the #1 side (I would have to assume that would be the drivers side). To compound the problem, the #1 side is adding extra fuel at the injector (long term fuel trim). That seems to explain why my mileage had dropped off.
We are going to start swapping O2 sensors around to see if the problem follows the O2 sensor; starting with the rear ones. The bummer of the whole deal is that it is a one tyr per day project because of the heat under the cats.

I was working on a 1998 Sub. last year and I had to remove the MASS AIR SENSOR and duct assy. I don' t know if it was me or the person after me who could have done it. The owner was having the same problem you where. The problem was the duct work was not tighen down near the intake manifold. Someone at Auto Zone found the clamp loosen. What happen is air is being bypassed around the MAF sensor so the computer thinks its not under a heavy load. So you get no power. Hope this helps.