Hello I have a 2003 Ram 4.7L.

First off I am an auto technician so I am not completely lost, but 90% of what I work on is foreign cars. This is my personal truck, and my first go with the 4.7L engine.

I purchased the truck running, but with a blown headgasket. There was a questionable engine noise which may have been bearings, but not loud enough to give me a huge cause for concern. Money is tight so I decided to try to get away with just replacing the headgasket.

I completed the job and it starts right up, but idles at around 3300rpms. When you give it any gas it just bounces off 3500rpms as if its stuck in some kind of limp mode. The motor seems to sound OK though its difficult to hear with the high idle, there are no signs of any other damage.

The only code I get is a P0016, Cam/Crankshaft position correlation sensor. Both the cam and crank sensors seem fine, wiring is fine, and they were fine before. Throttle body, IAC, TPS all seem to be OK. I think the cam code is an indication it jumped time, however I have never heard of an increased idle from jumped time, and it seems to run OK. Maybe I have more than one problem but I would really like to figure out the idle.

 

4.7's are bad about blowing head gaskets so thats nothing new.

Try looking here and see if any of this helps

https://dodgeforum.com/forum/3rd-gen...m-alldata.html

 

Update, I went back in and verified all timing is correct, replaced a faulty coolant temp sensor, started it back up and its even worse. Just goes to 3500 and bounces off like a rev limiter. The only code this time around is P0121- TPS/Pedal position sensor. I replaced the TPS and no change. The only time I get it to come down is when I shift into drive. When I shift into Reverse it goes even higher, to like 5500rpms. I'm running out of ideas.

 

I don't know 4.7 engines, but it sounds like it is actually hitting a rev limiter. I not certain but I believe there actually is a rev limiter for both Park, neutral and reverse. Have you checked the TB to see if it is actually closed. Maybe an adjustment is holding it open? IAC (Idle Air Controller), TV cable, TBS? IAC is controlled by the PCM and adjusts the idle for varios conditions such as cold engine, AC, chopped throttle.

good luck.....

 

Oddly enough it seemed to have been the PCV valves. Both were completely shot and as soon as I replaced them I was able to get the idle completely down.

 

Great.. well done

 

I wasd thinking vaccum leak, but clogged pcv valves would cause a high idle as well.
Thanks for atleast updating your thread.
I would do a resistance check on both your crank and cam sensors and backprobe them for their output voltages just to narrow the code down.