I found this for forum after looking for a solution to a problem I am having with my 2006 ram 1500 4.7 2wd and found a thread where somebody posted the exact same problem I'm having. Just curious if anybody has found a solution to this problem but I'm at wit's end trying to figure it out. It's only happens once the truck has reached operating temperature it doesn't do it all the time but it happens I often enough to drive me nuts. When coming to a stop the RPM will drop down to 700 RPM then over there for 5 or 6 seconds then slowly drop to 500 and sometimes 450 where a check gauges light will start blinking and oil pressure gauge start fluctuating.. I'm assuming the fluctuating oil pressure is because of the low rpms, it never moves any other time. if I cut my wheel to the right or left real hard the RPMs will go back up, sometimes, where it will stay until I go again and get to the next stop.. or if you bump the AC switch on real quick and turn it back off it will jump back up as well. I have checked every ground I could find, all the wiring, all the fluids are topped off, ran fuel injector cleaner through it, engine runs smooth and full of power otherwise. Tried posting a video but it's not the accepted file type so I'm doing a Google photos link to the video. Also there's a link below to the Post someone else made that I was referring to. Not sure if it's this same forum or not. Thanks for any help.

https://www.dodgetalk.com/threads/rpm-oddity.253146/

https://photos.app.goo.gl/9Gy1z91b63FrjBb38

Update, dropped the truck off at a shop 3 weeks ago. Got a call Friday saying it drove them crazy trying to track it down but came down to a bad oil pressure sending unit, total cost $114. Funny because I replaced that oil pressure sensor for that very problem but it persisted. I must have bought a bed sensor from autozone, although they said the part they bought was from AutoZone as well. RPM still drops to around 500 but that's as low as it gets and more pressure stays the same, no warning light or anything.

 

Does the CEL come on at all??

Likely a bad connection at one of the sensors, or a failing sensor. Fun part is figuring out which one.... Do you have a scanner that can read live data??

 

No unfortunately I don't have a scanner that can read live data just an old OBD2 scanner. I'll probably end up taking it to a shop and letting them figure it out. I'm old school, always owned older trucks this is the newest truck I've ever owned and these electronics a freaking nightmare for someone like me

 

Yeah, these days, if you wanna work on 'em, a decent scanner is pretty much a requirement......

 

If I remember correctly, and without bothering to look it up, I think there was a TSB and possibly a software update to address an issue with the PCM undershooting the idle RPM.

 

I'm having same problem.When I let the rpm drop super low I can hear a faint knock also.Ive replaced the oil sensor so today I'm going to take my oil pan off and see if maybe some rtv sealant is clogging up the pickup screen.Someome in another forum mentioned th oring from the pickup tube to oil pump and even a crank bearing blocking the oil galley but I m not sure.Its definitely a head scratcher.Luckily I have a manual transmission so revving up isn't an issue but still bothersome. Would love to hear if you've found out anything g with yours.I have the 3.7

 

now I haven't figured it out yet. I plan on taking it to a shop this coming week and dropping it off letting them figure it out with a modern scanner. I replaced throttle position sensor, couple transmission sensors, clean the throttle body, all fluids are fairly new and up to capacity, grounds checked, alternator checked at autozone, etc

 

Well I hope you're able to get it fixed I'm still being hard-headed and not taking it to no mechanic I've learned how to rebuild the engine with my 3.7 so I figure I'll keep at it for a little while trying to figure it out.And it only does it when it's warm so if you don't mind let me know the me mechanics professional diagnosis. My buddy has a real good scanner but I don't know how to use anything so it wouldn't really help me much cuz I borrowed it and didn't really understand what I was doing with it anyway like I said good luck with that have a good one.

 

Will do for sure!