QuestionThank you for the update. I am trying to find a troubleshooting flowchart to follow for the EGR system. Every repair manual that I have examined does not cover the EGR system. I have found a shop manual on Ebay for sale. Would this have the fowchart or is there another source?
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Followup To
Question -
When my 1997 villager rolled 100,000 miles, the check engine light came ON. It was carried to a local mechanic for service. It has been returned 4 times, but the mechanic cannot isolate the problem. I am told that all parts for the EGR system have been replaced.
I bought a code reader and have cleared the P0400 code twice. So far the code has not changed. It appeared after about 120 miles were driven each time. I am recording the information to see if anything changes.
Gas milage has not changed still ~23mi/gal; good idle
Does anyone have any ideas? I was told that the car was safe to drive, but I want to be sure.
Answer -
Shelton,
Yes, the vehicle is safe to drive but you are going to fail the smog test next time you have to go in for one. The code says that the EGR system is not working and that could be a clogged system from carbon buildup or the sensor that reads that it is working or the EGR valve itself. I assume that it is not coming on since you say the vehicle performs properly. So, it is a matter of going through the systems to see which part is not working properly or if the exhaust path is plugged up.
AnswerShelton,
Go to Nissanusa.com and download the .pdf file for the egr system as it is the best manual out there. I would diagnose the system myself if you could or have another shop give it a try as it could be as simple as replacement of the egr valve or as complex as taking the intake off and cleaning out the pathway for the exhaust gas.
