I need a little help I have a 2005 Dodge Ram 3500 with a 5.9 Cummins and I have never had any problems with it until about a month ago when i come to a stop light and have to sit there a few minutes the truck RPM's will start to jump up about 200 rpms and then drop back down this will go on for a couple of days and then go away for a couple of day only twice I have had a check engine light for low fuel rail pressure P0087 I have replaced the fuel filter,oil and the FCA (fuel control actuator) and the problem still continues I have 2 local dodge dealers but I don't trust them for poo has any one else experienaced this problem I am a do it your selfer and get along pretty good any help would be great thanks any one

 

Welcome to DF

I don't show any code P0087 in my service book, But there is a code P0088 for a fuel rail pressure signal is above max limit. But I will move your post to the 3rd gen ram section.

 

Any modifications done to your truck?

This might be as simple as a flash update from the dealer or a programmer website if you have it tuned.

 

no mod's to this truck bone stock and I called the dealer to see if there were any recalls but they say that i'm all up to date but I didn't ask them if there were any software updates maybe i'll call them back to ask but they are not very helpful when it come's to getting any info they are very tight lipped this problem is starting to drive me up the wall I had a guy want to race me today at a light because of the surge in RPM's, LOL a stock dully verce a camero really I just smiled and waved

 

You might want to have a smoke test done to check for vacuum leaks, that can definitely cause the issues you're describing and those pesky vacuum leaks can be pretty hard to find.

You might also want to check your intake and air filter out, you might have a very dirty air filter which is causing the engine to "choke"...

If you live in a coastal area or an area near water, or have backed your truck into the boat ramp a little too deep you might have gotten Water in the fuel tank, which can cause issues as well.

Just a thought too, did you follow the owners manual procedure when changing the fuel pump and made sure you bled all the air out?

Things I'd check next are:

Lifter Pump
Battery (if it's old try swapping it with a new one)
PCV Valve
Injectors - Might want to consider sending them out to get sonic-cleaned [if you can deal without a truck for a week or two]
Fuel Lines - you might be sucking in air somewhere which is causing "hiccups" in the fuel delivery.
Heater Grids - Might be kicking on and off or something... you can check that by pulling the relays for them once the truck is running and is at operating temp.

 

I'm guessing possible air leak in the fuel system, or like Izero said, dirty injectors. Diesel isn't a solvent like gasoline is. There are lots of helpful vids on youtube on cleaning diesel injectors, but if you can afford the downtime, sending them out for ultrasonic cleaning is best. I know you can buy rebuild kits to and just rebuild the injectors. Depends on how much fun you want to have.

 

Do you still have the lift pump under the hood or the updated fuel pump in the fuel tank? After looking for your code P0087, I see the code for the 2007 thru 2011 6.7 diesels. But not for the 5.9.

 

The truck has never seen water other than rain the fuel pump is in the tank I cleared the code and haven't had the light come back on yet so that I can verify the code # but am sure that it was for low fuel rail pressure and I have been running ATF every 3 tanks of fuel due to California Diesel is very dry Has very little lubricating value I have never had any issue with doing this I think I will check the heater grids next they have never been touched truck sitting at 159K thanks guys really appreciate the help

 

I've heard mixed reviews on using ATF in the fuel tank... maybe you should try using a lubricating additive that is meant for that purpose instead of ATF... your problems might be due to that ATF fluid... as it's not exactly meant to be used in that manner.

 

I have heard that too but I've been using that in all my trucks and it seems to really help especialy the duramax I think that I have found my problem what is your thoughts in the past week or so I have discovered that the problem happens only when fuel level is lower so I dropped the fuel level to about an eighth of a tank and the problem gets really bad mainly when i slosh the fuel a way from the pump in the tank I beleive the fuel pump in the tank has an air leak of some sort because I can get it to act up more by sloshing the fuel around