This is my first post to this forum. I hope somebody can help me.

2003 Ram 1500 - 5.7 Hemi

Sitting at idle it goes from 800 to 1200 rpms. When it goes up to 1200 it'll stay for about 5-10 seconds then back down to 800 for 5 seconds them back up to 1200. Does this constantly. Didn't start this until I replaced all 16 plugs/wires and cleaned throttle body and map sensor a week ago. Also sometimes just driving it'll start running real rough, no power at all and the red lightning bolt light will start flashing on the dash. I pull over to the side of the road, turn the switch off and then start truck again and it's fine. This has been going on for over a year. Somebody said it's the throttle position sensor, I bought one, said for that year and motor. Found out that the tps can't be replaced. It's built onto the side of the throttle body.

Any help please?!

 

Right church , wrong pew . You need the 3rd generation forum

Still , I will comment .

Possibly defective parts
Not sure if that throttle body has IAC or not , it may need to be cleaned
Was the battery disconnected when you cleaned everything ? It should have been .
Also somewhat characteristic of a bad 02 sensor

Good luck on the other side of the fence

 

Yeah I just realized that. Sorry. I have a 97 too. I re posted in Gen 3.

Throttle body was taken off and cleaned real good. No battery was not disconnected during any of it. And check engine light is not on so I can't check for any codes.

 

Vacuum leak. Go back over your work.

 

The throttle works off vacuum too?

 

A vacuum leak will confuse things, and sensor readings won't stay consistent, so, the engine will 'hunt' for the correct idle RPM. (and won't find it. )