Hi
I new to the forum but I have been on others for harley for years. I have a 1997 ram 164000 miles. It started a rough idle and so all plugs and wires also cap and rotor were replaced. Didn't help. The scan says no cylinders are misfiring but it is rough at idle and smooths out will speed. I was going to check the fuel pressure but there is no fitting on the fuel rail anyone know where else to check for the fitting I have been told they are on the drivers side rail. It seemed to me that this all started after running low on fuel.

sounds like your fuel pump is going i just replaced mine last week cause mine was doing the same for a awhile.....there is no schreoder valve on the fuel rail in 97's......mine really started doing it anything under a half tank....the pump is working alot harder because of the pressure and it dont cool as well because of the low fuel....i paid $224.60 out the door for a improved design Airtex pump from Oriely auto parts it was the best price i found...it is faily easy to change maybe a Hour to a hour and a half....

Sounds more like a dirty throttle body/IAC to me. Problems at idle that disappear at speed are usually IAC related.

when he said it gets low on fuel it does it........but that's a good call clean the iac and throttle body first (wont hurt...but it still leads to fuel pump symptoms when it does it on a low fuel tank...

Said it started after fuel got low ... I assumed he got low once and then it started. Coulda picked up some crap from the bottom of the tank that made it through the filters and jammed up the IAC.

Sorry I can't type it's a 5.9 engine and it just seemed to start when I ran it low. There is no change in the way it runs even with a half a tank. At idle the truck just sits there a shakes when you give it some gas it seems to get better. Sometime at idle it is worse than at other times.

After 164k it could be crap in the cell. Especially if the problem just arose after having run low on fuel. Even though you have no schrader valve you can still pinpoint the problem before just throwing money at it.Take your fuel pump relay out and crank the motor for a several turns. This should aleviate the pressure on the rail into the cylinders.You may get a code, but you can clear that later. You can then disconnect the line from the rail. I would still cloak the fitting with a rag to make sure you don't get any spray on your face. Did I mention, don't smoke while you do this. With the key off, put the relay back in. Put the removed fuel line into a mason jar and have your wife/friend/neighbor turn the key to the on (not start) position. Then observe the stream that comes out. If it seems weak, then the problem is in the regulator or the pump. If it does not you can remove the rail and injectors from the rail and give them all a thorough cleaning. I think it was VWand Dodge?? that did a write up on cleaning the rails and injectors. His were pretty bad.

About the shrader valve on the fuel rail...there isn't one

They came on some models/years but not others. I dunno if its safe to say there not on any '97 but theres not one on mine either.