My check engine light came on 2000 Lumina with a 3.1 SFI I got a CanOBD2&1 Scan Tool from Sears. I came up with code P0405 EGR Sensor A Circuit Low. I can not find any short circuits, diconnected wires, I tested the connecter going to the EGR as described in the Haynes manual and everything tested good. Does anyone have any Ideas?

 

Your Egr could most likely be bad.

 

Could a bad battery cause this problem? About the same time as the check engine light came on the car radio started turning itself on and switching to CD mode and weird stuff like that..I took the car to have the battery load tested today and they told me it was only producing 280 CCA

 

I put a new EGR in, now it's Oct and I have the same code Anybody else have any Ideas?

 

Almost every time a GM car comes in with a EGR code (po405) the valve goes bad and takes out the computer. It happens 9 times out of 10.

 

The light went out a couple of times, can an egr valve go bad in a couple of months? those things are $90.00 a pop thanks for your help.

 

first issue is usually the fuel cap.. check the seal around the fuel cap and make sure its locking down correctly.. then look for vacuum hoses that are cracked or leaking... then I'd check the the egr sensors (usually the sensors go bad first) and lastly the egr canister itself (a lot of times the plastic on it cracks especially with the temperature changing with winter)

 

Well, I cleared the code put a new egr on now I have a P0401, So I guess I have some cleaning to do