code P0401 EGR insufficient flow after replacing dash gauges

Eddie Mechanic Glendora, California Posted   Latest  
1997 Chevrolet Cavalier Z24 2.4L (T LD9) 4-spd (4T40-E)—1G1JF12T8V7333179

code P0401 came on after replacing dash gauges checked EGR valve seems to open on command engine runs rough while open

Brian Instructor
Parma, Ohio
Brian Default

I would not think that code P0401 in PCM is related at all to the cluster. Was battery disconnected when servicing the cluster? What is the EGR pintle position % when it is closed / koeo?

0 Default Ð Bounty Awarded
David Owner/Technician
St. Albert, Alberta
David Default

Good advice from Brian. Was any other work done at the same time? Does EGR kill the engine with scan tool activation, it should.

0 Default Ð Bounty Awarded
Michael Diagnostician
Vineland, New Jersey
Michael Default

P0401 is a flow problem pull egr valve see if it is carboned,see if it will run with valve removed,ports are clogged to some extent,should stall with valve off​.​HTH

0 Default Ð Bounty Awarded
Paul Mechanic
Harvey, Illinois
Paul Default

Came on after or was the CEL not working prompting gauge replacement? Most likely cause is restriction given age of vehicle. Should come close to killing if not killing engine at idle.

+1 Default Ð Bounty Awarded
Troy Owner/Technician
Longbranch, Washington
Troy Default

I would have to think that maybe it was there and after repair things are working or reporting, could be luck of the draw as well, dont know but i always do a complete vehicle scan these days as you know ever since you put air in my tires my wipers dont work

0 Default Ð Bounty Awarded
Eric Owner/Technician
Edgerton, Wisconsin
Eric Default

P0401 is a low EGR flow code. The replacement of the instrument cluster had nothing to do with the setting of P0401. Opening the EGR valve at idle should kill the engine, not just cause it to stumble or run rough. If the engine doesn't die then either the EGR valve is not opening all the way or the EGR valve passageways are restricted or plugged.

+1 Default Ð Bounty Awarded
Steve Instructor
Irvine, California
Steve Default

Why was the cluster replaced? Were there any codes in the ECM prior to repairs?

0 Default Ð Bounty Awarded