Doug Larson
Junior Member
- Joined
- Jun 9, 2018
- Posts
- 3
- Reaction score
- 0
- Location
- Mankato, MN
- Ram Year
- 2002 (2nd Gen)
- Engine
- 5.9L 360ci Gas
I just replaced the heads on my 02 2500 5.9 ltr Magnum. I learned that the cadylitic converter was plugged so I cut that out. I've replaced every sensor on the truck but it still idols rough and runs rich. Around 5 to 6 mpg. I keep getting a P0121 code and I just noticed my fan is constantly running. I heard I have to reset the ECM but no one has ever explained the process step by step. I have been removing the engine control 1 and engine control 2 fuses from under the hood, turning the key to run and waiting roughly 15 seconds for it to read "No Bus" then ding twice. Then I do a 12 second key on before starting. Is this right because it's not working. I've even disconnected the negative battery cable before anything and still no difference. Is this something I can do without a scanner or do I need to bring it in?
