I have a 2001 LSE that keeps giving the garages in my area a defective egr valve code when they hook up there electronic tester. I replace the EGR valve with a new one and reset the computer but the check engine light continues to come on and after taking it back to the garage they still tell me the computer shows a bad egr. I don''t think the new egr valve could be bad also. Any ideas or suggestions?


The check engine light does not stay on all the time. It seems to only come on when the fuel gauge goes below 1/2 of a tank. My gas milage seems to be down also. 17 MPG vs about 20.

 

For the EGR valve, you probably have a plugged tube in the intake manifold, not too hard to clean..
http://isuzufaq.ibctech.ca/#faq1

Fuel level shouldnt have an effect on the EGR code, thats a weird one. You will get a CEL on low fuel level if the fuel sending unit is going bad. But if the gauge seems to be working right the sending unit should be ok.

Decreased fuel mileage could be the result of winter blend gas depending on what they use where you live. Here in Denver they put 10% ethanol in the gas in winter which will decrease fuel mileage a few mpg.

 

My 99 was doing the same.It ended up being carbon buildup in the intake and the egr ports.cleaned all that and now seems to be fine except for my door lock issue no one can help me with..