DODGE RAM FORUM - Ram Forums and Owners Club! - Dodge Truck Forum

Go Back   DODGE RAM FORUM - Ram Forums and Owners Club! - Dodge Truck Forum > Dodge Ram Forum - Help Zone - Dodge Ram Problems, Complaints, & Solutions - Maintenance & Re > 3RD Generation Dodge Ram 2002 to 2008 Dodge Ram Trucks > Powertrain > 4.7L PowerTech V8 Specific Topics


Notices


Latest Vendor News
AutoAnything
Addictive Desert Designs!
Bayou Goat Mounts

Reply
 
Thread Tools
  #1  
Old 07-18-2011, 05:05 PM
el profe el profe is offline
Dodge Ram Forum Newcomer
 
Join Date: Jul 2011
Location: Turlock, CA
Posts: 6
Gender: Male
Vehicle: 2002 dodge ram
Trim Level: SLT
Color: white
Engine: 2002-2007 287ci (4.7L) PowerTech V8 235hp 295lb/ft
Rep Power: 0
Rep:10
el profe is on a distinguished road
Default RPM fluctuation out of control

Hey everyone, brand-spanking new here (signed up today 7/18) glad I found this place and hopefully it'll keep me from parting with my ram(02 4.7). For at least a couple of years now my idling has been out of whack. when I start the truck in the morning it revs up to about 2500 rpm and then it starts to fluctuate down to 1000, then back to 1500 then down again and so on and so on to eventually it goes down to about 600. I'll drive around and when I put in in park the rpms will shoot up again. when on the freeway cruising about 65 the rpms go from 2000 to 2500 back and forth. any help would be greatly appreciated, thanks a lot.
Reply With Quote
Sponsored links
  #2  
Old 07-18-2011, 05:35 PM
starquestbd22's Avatar
starquestbd22 starquestbd22 is offline
Dodge Ram Forum Senior Member
 
Join Date: Jan 2011
Location: NC
Age: 32
Posts: 2,673
Gender: Male
Vehicle: 2004 Dodge Ram 1500 4X4
Trim Level: Sport quad cab
Color: Bright Silver Metallic
Engine: 2003-2008 345ci (5.7L) Hemi V8 345hp 375lb/ft
Rep Power: 6
Rep:367
starquestbd22 is just really nicestarquestbd22 is just really nicestarquestbd22 is just really nicestarquestbd22 is just really nice
Default

Welcome to the forums! Don't sell your Ram. We are here to help (or at least try, lol)!!!!!

I have a 2006 4.7 and I have had a similar issue but not as bad as yours. A couple of times I have started the truck and got the same thing you describe....the normal high warm-up idle, dropping back down to close to normal, then back up and down two or three times before finally leveling out.

Also, sometimes it idles great and what I consider normal but sometimes while stopped in traffic it will idle considerably lower (prob 400 RPM or so). Doesn't seem to fluctuate really and has never died or idled so low that is started running rough.

So sounds like mine might not be as progressed as yours but I'm thinking same issue. I ran some seafoam through the intake about a month ago and noticed no real change. I changed the plugs and cleaned the throttle body this weekend and it made the engine run smoother in general but did nothing for the idle issue. I am considering replacing the idle air control valve first and then the throttle position sensor if that doesn't fix the issue. The IAC valve is made so that you really can't clean it.

I can't think of anything that is a more likely culprit than the IAC valve and the TPS. They are about $66 and $33 respectively so I hate to replace them on a whim. I will update if I do and maybe someone else can add some suggestions in the meantime.
__________________
06-08 chrome clads w/33" Cooper Discoverer H/T Plus, Mopar tailgate spoiler, debadged door trim & tailgate emblems, 13" antenna, LED dome & maps, Magnaflow 22" SI/DO, 18% tint, "HEMI" hood spears, VHT tinted tails & third brake light, Lamin-x optic blue fogs, leveled w/McGaughys 2" drop shackles.

Last edited by starquestbd22; 07-18-2011 at 05:37 PM.
Reply With Quote
  #3  
Old 07-18-2011, 06:27 PM
el profe el profe is offline
Dodge Ram Forum Newcomer
 
Join Date: Jul 2011
Location: Turlock, CA
Posts: 6
Gender: Male
Vehicle: 2002 dodge ram
Trim Level: SLT
Color: white
Engine: 2002-2007 287ci (4.7L) PowerTech V8 235hp 295lb/ft
Rep Power: 0
Rep:10
el profe is on a distinguished road
Default

thanks for the welcoming and the quick reply! yeah, thanks for the great info. let me know how it goes and perhaps like you said, someone might add to your suggestion to my problem.
Reply With Quote
  #4  
Old 07-19-2011, 07:57 AM
mclovin7794's Avatar
mclovin7794 mclovin7794 is offline
Dodge Ram Forum Newcomer
 
Join Date: Jun 2011
Location: Anchorage
Age: 25
Posts: 25
Gender: Male
Vehicle: 2002 Dodge Ram
Trim Level: SLT
Color: Grey
Engine: 2002-2007 287ci (4.7L) PowerTech V8 235hp 295lb/ft
Rep Power: 0
Rep:10
mclovin7794 is on a distinguished road
Default

Greetings and welcome,

I had a similar issue (but not as bad as yours) and I had to replaced the gas cap and that helped. The rubber seal around the cap was broken and it also set off a check engine light. The gas cap was about $12. Might be something to check into. Good luck.
__________________
Grab life by the horns.
Reply With Quote
  #5  
Old 07-24-2011, 12:21 PM
bigdaddyII's Avatar
bigdaddyII bigdaddyII is offline
Dodge Ram Forum Senior Member
 
Join Date: Sep 2009
Location: Southern, Louisiana
Age: 32
Posts: 565
Gender: Male
Vehicle: 2012 Ford F-150
Trim Level: XLT
Color: Metallic Blue
Rep Power: 6
Rep:91
bigdaddyII will become famous soon enough
Default

I had the same issue with my 02 a few months ago. It would do the same thing you describe but when I would stop at a light it progressed to the point that it would idle wildly. The RPMs would fluctuate from 500 to 2200 while sitting there. I never considered it to be a sensor because I did not have a check engine light. I had recently cleaned the TB when it started doing this so I took it apart again thinking the seal may have been messed up. It ended up being the throttle position sensor. I bought a new one at AZ ($35 or so) and the truck has never idled so smooth.
__________________
Sure it'll suck, but it'll make you a man
Reply With Quote
  #6  
Old 07-24-2011, 12:40 PM
starquestbd22's Avatar
starquestbd22 starquestbd22 is offline
Dodge Ram Forum Senior Member
 
Join Date: Jan 2011
Location: NC
Age: 32
Posts: 2,673
Gender: Male
Vehicle: 2004 Dodge Ram 1500 4X4
Trim Level: Sport quad cab
Color: Bright Silver Metallic
Engine: 2003-2008 345ci (5.7L) Hemi V8 345hp 375lb/ft
Rep Power: 6
Rep:367
starquestbd22 is just really nicestarquestbd22 is just really nicestarquestbd22 is just really nicestarquestbd22 is just really nice
Default

Yeah, no CELs here either but I'm fairly confident it is a sensor issue because of the fact that it is rather sporadic. Sometimes it idles/runs perfectly smooth. If it were a mechanical issue I think it would have the issue all the time.

I think I'm going to replace the TPS first (because it's cheapest, like you said about $35) and if that doesn't fix it then the IAC valve (about $66). I wonder what the return policy is on electronic sensors like that? I would assume they are non-returnable. I hope that will fix it but if not it's only $100 and I have two new parts on my truck I guess.

I will probably try to do this some time this week. Will update when available. It may take some time for me to figure out whether or not it fixes it though because like I said, the issue is sporadic and I sometimes go a whole week without driving my truck.
__________________
06-08 chrome clads w/33" Cooper Discoverer H/T Plus, Mopar tailgate spoiler, debadged door trim & tailgate emblems, 13" antenna, LED dome & maps, Magnaflow 22" SI/DO, 18% tint, "HEMI" hood spears, VHT tinted tails & third brake light, Lamin-x optic blue fogs, leveled w/McGaughys 2" drop shackles.
Reply With Quote
  #7  
Old 07-24-2011, 10:24 PM
bigdaddyII's Avatar
bigdaddyII bigdaddyII is offline
Dodge Ram Forum Senior Member
 
Join Date: Sep 2009
Location: Southern, Louisiana
Age: 32
Posts: 565
Gender: Male
Vehicle: 2012 Ford F-150
Trim Level: XLT
Color: Metallic Blue
Rep Power: 6
Rep:91
bigdaddyII will become famous soon enough
Default

I forget where I heard this, it may sound crazy but there is a bit of truth in it. Take the TB cover off of the truck (cover that says 4.7 Magnum) and start the truck. While the truck is idling tap on the TPS with a screw driver. If the idle changes thats the bad sensor, if not its fine. I tried this when I bought and was ready to swap mine. The truck happened to be idling fine, I tapped it and it suddenly sounded like an airplane gaining altitude. Tried it after the sensor was changed out and no change in idle.

I think the logic is that something is shorting in it if you can tap it and the idle changes as its only an electric switch and only supposed to "open" when it is turned, in turn changing the idle. Just something to try if you have a minute or get curious.
__________________
Sure it'll suck, but it'll make you a man
Reply With Quote
  #8  
Old 07-25-2011, 03:56 AM
Dodgerman1 Dodgerman1 is offline
Dodge Ram Forum Junior Member
 
Join Date: May 2011
Location: Tullahoma Tn
Age: 21
Posts: 49
Gender: Male
Vehicle: 2002 Dodge Ram 1500
Trim Level: SLT
Color: Midnight Blue
Engine: 2002-2007 287ci (4.7L) PowerTech V8 235hp 295lb/ft
Rep Power: 0
Rep:22
Dodgerman1 is on a distinguished road
Default

throttle body position sensor. should throw a engine code in time. but mine was doing that and its a 32 dollar part a like 2 bolts to take it off.
Reply With Quote
  #9  
Old 07-28-2011, 08:07 PM
el profe el profe is offline
Dodge Ram Forum Newcomer
 
Join Date: Jul 2011
Location: Turlock, CA
Posts: 6
Gender: Male
Vehicle: 2002 dodge ram
Trim Level: SLT
Color: white
Engine: 2002-2007 287ci (4.7L) PowerTech V8 235hp 295lb/ft
Rep Power: 0
Rep:10
el profe is on a distinguished road
Default

bigdaddyII, interesting you said what you said about tapping the sensor because one of the the symptoms that I have noticed over time is that when the truck hits a bump, a pot hole, or unevenness on the highway, the rpms will shoot up as if triggered by a sudden "hit" or movement by the truck caused by the road. as if the sensor is shorting. I thought I throw this in.
Reply With Quote
  #10  
Old 07-28-2011, 08:19 PM
el profe el profe is offline
Dodge Ram Forum Newcomer
 
Join Date: Jul 2011
Location: Turlock, CA
Posts: 6
Gender: Male
Vehicle: 2002 dodge ram
Trim Level: SLT
Color: white
Engine: 2002-2007 287ci (4.7L) PowerTech V8 235hp 295lb/ft
Rep Power: 0
Rep:10
el profe is on a distinguished road
Default

also, I bought the TPS sensor with the thinking like starquestbd22, replace both the IAC and TPS sensors and if it ends up neither is the problem, then I got myself two new sensors. Is swapping one sensor for the other all there is to doing this work? disconnect negative cable, unplug sensor, remove two screws, put new gasket and sensor and tighten, reconnect sensor and bat cable and that's it? any special things i need to do?
Reply With Quote
Reply

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
error code list moparmike07 Dodge Ram Knowledge Base 16 02-15-2014 05:16 PM
Temp Control Manogod Heating & Cooling 2 03-08-2011 06:05 PM
Talk about your good/bad experiences with stability control slikkwilly002 Dodge Ram General Discussion 7 03-06-2011 05:46 PM
dtc po148 nachizzle Cummins Diesel Specific Topics 2 06-09-2009 01:36 PM


Advertisement






All times are GMT -4. The time now is 09:20 AM.


= Copyright RamForumZ.com a Gigathreads.com Network Site =Ad Management by RedTyger
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2015, vBulletin Solutions, Inc.
vB.Sponsors


=Gigathreads Network=
CLUBS MOPAR NATION DSM GPMM MAMM JAM
DIESEL Diesel Forum      
CHEVY Chevy Camaro Forum Chevy Volt Forum    
CHRYSLER Chrysler 300C Forum      
DODGE Dodge Avenger Forum Dodge Caliber Forum Dodge Challenger Forum Dodge Charger Forum
  Dodge Circuit Forum Dodge Hornet Forum Dodge Magnum Forum Dodge Nitro Forum
  Dodge Ram Forum Dodge Dakota Forum Dodge Durango Forum Dodge Dart Forum
FORD Ford Raptor Forum Ford F150 Forum Ford F100 Forum  
JEEP Jeep Forum      
PONTIAC Pontiac G8 Forum      
SRT SRT Viper Forum SRT Cuda Forum