How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask John Your Own Question
John, Master A.S.E Automotive technician
Category: Chevy
Satisfied Customers: 9176
Experience:  A.S.E MasterTechnician A1-A8 w/L1,38 years experience General Motors Master Technician
Type Your Chevy Question Here...
John is online now
A new question is answered every 9 seconds

2003 impala: flow..replaced the egr valve.

Resolved Question:

my 2003 impala has code po401 insufficient egr flow. I have replaced the egr valve. What else could be wrong?
Thanks, Ron
Submitted: 6 years ago.
Category: Chevy
Expert:  John replied 6 years ago.



This condition is caused by a restriction of the drilled hole in the upper intake manifold being plugged with carbon.Remove the EGR valve & clean the carbon out with a flexible small brush or similar tool.Residue should come out in the intake .I remove the throttle body to get easy access to the EGR internal port,better cleaning the chunks than running them through the engine.

John and 2 other Chevy Specialists are ready to help you

Related Chevy Questions