Hello, first time post here. I have a 2003 2500 with the 5.7. Its fairly new to me and had been running fine up until two days ago. Has 126k. The CEL came on at the same time the Red flashing lightening bolt. Truck started running really rough, seemed like it wasn't shifting into overdrive on highway. Pulled over, shut it down, restarted. Same thing in less than .5 mile. Made it back home and plugged in my Edge, first time on this truck. p2106,2138,0443,0300,0306. Took off the Throttle body and cleaned it well, it was filthy. Checked the connections and they seemed fine. All back together and same thing happened again. Rechecked codes and the 2106,2138,0443 were back. I am leaning towards the evap solenoid/valve being faulty but before I start throwing parts on a guess I thought you folks may have some better ideas.

 

I don't think a 0443 code would cause the 2138 code. They could both be related to a bad electrical connection at the PCM. There are diagnostic procedures for both 0443 and 2138. I would think you either have an electrical problem or the PCM is damaged.

 

Thanks for your thoughts, they make sense, was hoping not to hear that. Lol. When you say diagnostic procedures, do you mean on this forum they are available? I have messed around a little with pins on a PCM of a larger truck, but honestly don't even know where its located on this 2500. I'll start by finding it and looking at all the wiring for shorts etc.

 

The factory service manual has diagnostic procedures. There was online versions posted on the forum not sure if it still works. I have never probed the PCM connectors. You are supposed to use a special breakout box so that the PCM connector is not damaged. Both the evap and throttle control sensor come in on the C3 connector. The PCM is on the firewall on the passenger side.

 

So I tested the plug at the evap solenoid valve and I am not getting power on either wires with koeo. Do you know if there is a relay or fuse that may need to be checked or replaced? I haven't seen anything on the fuse box cover that shows evap solenoid.

 

On the 2005 both the control and signal go to the PCM. You need a scan tool that run tests to actuate the solenoid. You need some very good electrical diagnostics. It may turn out to be the PCM but they should verify the PCM has clean connections to the fuse box. They have been known to cause problems. You can ohm test the purge solenoid but I don't know the specs for it, but maybe 15-30 ohms. But with your P2138 code I would expect something more common with the PCM either bad connections at the PCM or Fuse box or a bad PCM. Good luck hopeful you can find a good mechanic.