Hello. I just registered today in hopes I solve an issue with my 2003 Dodge Ram 1500. I purchased it 3 1/2 months ago and in the past month the truck has developed a surging symptom. It will drop down from 1,000 rpm to 500 and even lower when idling in park, neutral, drive and reverse.

One of my buddies say it very well could be the fuel pump. The truck has 84,400 miles. Everything seems stock. I bought the truck as is. The only addition was a Flowmaster muffler with pipes and accompanying tips which were there when purchased. I've changed the air filter out and it was the factory piece, so that leaves me to believe nothing else has been touched. Just today I swapped out the battery for a Maxx from Wal-Mart. It still surges. On a side note, the check engine light went off after the installation. It's been on since purchase.

I went with a new battery since I watched the lights and battery gauge flicker when the truck would surge, hoping it could possible be the battery. I've thinking either the wires or the alternator could be at fault. I would like to properly diagnose it, however, I'm not sure where to start. I came here to hopefully find somebody that could lead me the way to the source or has had the same problem.

The engine is a 4.7.

Thanks for the help,

Adam

 

500 is a normal warm in gear idle...mine idles at 500 and 600 with the a/c on. If it fluctuates then you have a problem. That being said, with 84k on the clock it's due for a good throttle body cleaning. Remove it and clean with carb/throttle body cleaner.

Wait...i'm lost. So it's surging? Clean the throttle body and if it was me i'd just replace the TPS and IAC valve (or clean...don't move the spindle though)...they're both decently cheap.

 

Does the 03 4.7L have an IAC? if so, it is probably sticking.

 

I had this same problem a few months ago. I cleaned the throttle body and took the IAC Valve out of the throttle body and cleaned it as well I used carb cleaner and shop towels. There was a big piece of carbon buildup on the end of the IAC Valve when I took it out. That fixed my surging problem hope it helps you out. This is a great site for things like this.

 

Hello all. Thanks for all the help. I did some research on the IAC valve and I'm pretty sure that is the source. I purchased some torx bits yesterday since that is what it will take to remove the valve. I have yet to do so.

I'm new to vehicles equipped with these senors and valves. I've been dealing with carburetors. After I purchased the truck I did purchase some octane booster and Lucas' Tune-Up in a bottle, which I'm sure broke up the deposits and probably left some clogged in that valve. Before I tear into the valve, I'm going to try a gas treatment to see if that will clear up the dissolved deposits.

At my recent oil change I used Valvoline Syn-Power oil and Gumout's All-In-One fuel system cleaner. I plan to stick with a gas treament every fill up. I have a can of throttle body and air intake spray to clean out the ICA valve when I'm ready.

Once again, thanks for the replies.

Adam

 

I've been having some hesitation and some weird idling with my 4.7 too. I know this is crazy but I changed the oil to another brand than Mobil 1 and the mileage went down byalmost 4 miles a gallon. Which I’ve been told that should never happen . It’s still synthetic oil I use but I’m going back to Mobil one.

I have replaced the EGR valve and I have a K&N CAI that I cleaned and reattached it, so I know that was good to go. As for the Sea Foam how do I use it?? Do I pour it in the oil before the next oil change or do I add it to the fuel system in the gas tank??

What is the IAC valve, and where is it located.

 

Dont know if the '03 4.7 is like the 02 4.7 engine, but here is a how to on getting to the IAC
http://www.youtube.com/watch?v=5yStBpngvbs

 

i had this same problem mine was to the point where it would stall out sometimes once i took my throttle body out and cleaned it it worked perfect. if you dont wanna take it off thereis a producted called sea foam i guess a buddy of mine swears by it