GMS Sierra 1500 Code 0401

[Brenden Burnham]

Took in to get check engine light code and came back the EGR Valve(0401).  My question is it typically for these trucks is it usually just a bad EGR Valve or is it often something else maybe the connector, etc?  Is just a 10 minute job(if that) to replace so of course is going to be the first thing I will do but if that is not what else should I check?  Seen videos of them testing using a pressure tube but these do not seem to be like the old style EGR's where it had the port on top to test with.  Also seen some things about testing the DPFE Sensor, is that the thing that plugs into the EGR valve itself or is it located somewhere else??  Couldnt really find anything on the location of the DPFE Sensor. 

 

So first I am going to replace EGR Valve.  If that doesnt solve it what should I test/check next?

 

Thanks everyone

[shakenfake]

Delete the EGR is the easiest way, just need the block off plates and a tune. If you were in TX I'd be willing to tune it for you. You would need a tune though to get the CEL to go away it doesn't need to be expensive and some shops would probably do it for cheap

 

I would not throw money at a system that was removed by GM and that does virtually nothing. Just my opinion though

Edited December 7, 2021 by shakenfake

[richard wysong]

if you do change the valve make sure the passages aren't clogged with carbon

[Brenden Burnham]

Sounds great.  Going to swap out EGR tomorrow and will update.

[Brenden Burnham]

Took about 10 minutes to install(most time came from finding my ratchet extension).  Checked and the passages were completely clear/clean.  Swapped out.  Kept old just in case was bad wire/connector somewhere.  Not even 30 minutes of driving the check engine light turned off.  Happy

[richard wysong]

great! easier than trying to eliminate it too

[shakenfake]

Definitely lucky on that one! My EGR bolts were so stuck in there that I just pulled the whole manifold off when I went to take mine out. I was deleting it anyways but still

[Supreme Pizza]

Its always nice when diagnostics and repairs go smoothly.