Hey guys its been awhile since i've been on here. My ram at idle at random times likes to idle at 600 rpms and then drop a little then it revs up to about 800 like its catching itself then does fine for a few seconds and does it again. It seems to do it worse with the compressor on, which is new. Has 110k miles on it. Original plugs. I know they are overdue, but i wouldnt think would cause idling issues. I'm thinking maybe clean the throttle body and seamfoam it and change the plugs. Anyone have and ideas?

 

That would definitely be a start, Pcv valve also and how's your air filter?

Do you have a check engine light? This surging is sometimes an o2 sensor.

 

When my 02 4.7 did that I didnt have a code and it ended up being my TPS. Before taking the TB off to clean it, start the truck and let it idle, then tap the TPS with a screwdriver, it is supposed to hold its idle. If it starts going up or down or changes drastically, theres your problem. Its a $30 part at AZ.

 

No engine codes. Filter isnt bad. What do you mean tap the tps?
thanks guys

 

I had the same issue a while back with no codes on my 4.7. It was the TPS, its easy to fix.

 

Remove the plastic cover that says "4.7 Magnum" and start the truck. TPS sits on the right side of the TB, with the truck idling grab a screwdriver and hold it in your hand the wrong way. With the end that you are supposed to be holding (if you were using the screwdriver the correct way) give the TPS a few love taps. See if the idle changes, if it does you are done, replace plastic cover and drive to Autozone, Napa, etc, and but a new one. If idle doesnt change, give it a few more love taps, still no change then cuss under your breath and continue your search for the problem.

 

You can also 'reset' the TPS by turning the key to on, wait for all the dinging and whatnot to stop, then smoothly press the gas pedal to the floor and release. Turn the key off, now the computer knows the full range of the TPS.

Sometimes this can get out of wack just jumping in the truck putting in the key talking to someone and playing with the pedals because you are not aware this is a programming method.

Your TB will need a cleaning anyway, but try and not use chlorine cleaners around th TPS, remove it if need be.

 

I see.... Will either be an okay cleaner? Thanks for the TPS advice. I'll check it. I've done the reset of the pedals before, but someone said on here thats for diesels only. That not the case? Thanks guys.

 

Use a chlorine free brake cleaner to clean the throttle body.