Alright guys, I'm fairly new to the site so take it easy on me. I acquired a 96 ram with the 5.2 through a trade and I'm trying to get it up and running correctly. It has the 5 speed also. When I'm driving it, I can't accelerate past 1/2 throttle without it backfiring in the intake or just completely not accelerating at all. It does have new plugs and wires. The fuel pump is making a hell of a whining and I'm thinking that is the issue but want other opinions before I take the bed off this thing to replace it. Even when idling, I have a hard time getting it up to 3k rpms. Any help would be appreciated. Thanks.

 

Take a look down the throttle body. If there is oil in the intake it most likely needs the air plenum gasket replaced. If that is the case do a search for the Kegger mod on this forum. It shows a good upgrade if you plan on keeping this truck for a while. The fuel pump could be a problem I don't know for sure how to check it without a pressure gauge. If you have the correct gauge you can check the pressure up by the intake. It should be above 30 psi if I remember correctly.

And welcome to the forums!!!

 

Sounds like timing. Not your fuel pump. Sounds like you have your work cut out for ya.

 

I guess that could be a possibility also. To me, it just feels like I'm not getting fuel at WOT but I guess it could be the timing. It runs fine as long as I just ease into the throttle but if I try and advance the throttle too fast, it backfires or does nothing. Just trying to get a good starting point tonight before I jump into it in the morning.

 

i have the same problem , i have replaced every sencor and fuel pump and still the samething , getting the computer checked tomorrow , if it works i'll let you know ...also had the timing checked all new plugs , cap , rotor , wires , i mean everything is new , just not the computer

 

It's got to be something simple or at least hope. I just picked it up this afternoon and it wasn't running. He couldn't figure out what was wrong with it. Turned out to be one of the main fuses under the hood. I don't think it's the PCM yet. Water pump gets replaced in the morning also.

 

Alright, I've checked the fuel pressure and it's only 25 psi and drops down to 20 when at 2k rpm's. I thought these trucks were suppose to be in the 40-50 range. I also got a CEL this morning. P0171 and P0138 both point to an o2. I will probably change the pump and see what that does. If that doesn't fix it, then I'll go to O2 sensor. Any other opinions?

 

It may be possible you are just experiencing an extreme lean condition due to a failing fuel pump. Several of the symptoms you describe point that way IMO. For one, any time you hear a fuel pump is a warning. Also your measured pressures are way low. The fact that when you are giving it gas and the prssure goes way down also not a good thing. The mid RPM bogging with backfiring sounds like an extreme lean condition as well. Finally, the codes, O2 related would seem to be pointing to a bad mixture, ie too lean. Before replacing O2 sensors, which may be functioning perfectly by dropping those codes BTW, try replacing the fuel pump and reevaluate. It could be that simply dropping in a new fuel pump fixes all that stuff IMO. Sounds like you've already proved you need one anyways from the fuel pressure test so you really have nothing to lose if you plan to fix it anyways.

 

your fuel pump is weak and its causing all your other problems. correct pressure is 49 psi

 

I can't remember where I read it at but I think it is supose to hold at least 30 psi for 5 minutes. I think it should normally run close to 50 psi.