po401

[winters32]

hello all,01 mounaineer 5.0.I have replaced the dpfe,and vacuum solinoid.Can manually ground solinoid from pcm,and my egr opens.I'm thinking I have a bad pcm.Any help?Thank you in advance...

 

[2000StreetRod]

PCM is very reliable

P0401 Exhaust Gas Recirculation Flow Insufficient Detected

In my opinion the PCM is the least likely item to fail. If the engine is running at idle does it die when you ground the vacuum solenoid? If not, your EGR valve is probably not opening enough. You can also test your EGR valve at idle using a hand vacuum pump.

EGR System O&T

 

[winters32]

401

yes the vehicle dies

 

[swetrid]

ck all the vacuum lines