Hi everybody, new here to the forum.
Hoping somebody can help me out with this.
1997 Chevy K1500 Z71, 5.7 litre. I keep getting this P0401 code that is "insufficient EGR flow." I have replaced the egr valve and cleaned all the egr passages. I have verified they are clear and I have verified that the valve is not stuck open or closed. I do not know how to check the pins on the wire harness to make sure that the power input to the valve is correct. I have tools, but I don't know what pin is what on the harness. I don't know what else to check, seems like it should be fine, but the code keeps popping back up. The truck does have an old battery and I use a battery tender on it. Starts, runs and drives fine, but I don't know if this could be messing with the computer???
Any advice is greatly appreciated,
Thanks,
Clay

 

That code is tied to map sensor also,meaning there is a conflict between the two, harness look ok?clean connections?and it's not messing with ecm,just alerting you of a error

 

thanks, do you know where the map is located on this truck?

 

On back of intake plenum?

 

found it, everything looks good, it tests out good. All the components here are good. I don't know if the PCM is sending the signal, and the truck has to be going down the road...

 

Try,easyautodiagnostics.com>egr-valve