1996 Es300 Excessive Egr Flow- Code 402

[mpringle]

I have a 1996 es300 that has a code # 402 = Excessive EGR Flow. I had the EGR valve replaced by a Lexus mechanic, however after a few weeks, the check engine light came back on with the same code. I'm not mechanically inclined, but I can do basic work on my car. What can I do to troubleshoot this issue? What might be the problem? Thanks ahead of time.

[RX300ES300]

There is a temperature sensor at the bottom part of the EGR, did the mechanic replaced it?? Double check with him, and how many miles after the replacement, the light went on again?

[mpringle]

There is a temperature sensor at the bottom part of the EGR, did the mechanic replaced it?? Double check with him, and how many miles after the replacement, the light went on again?

Not sure how many miles, probably about 200?

[George_Jetson]

Here is a description the code, along with the steps you should take to troubleshoot. Some steps require special tools, but I am sure that you could do some of the others.excegr.pdf

[RX300ES300]

Was the EGR temperature sensor replaced by Lexus mechanic??

Anyway you can check the sensor by measuring the resistance of the sensor. See George's attachment.