dan099

First off, I am a new lexus owner. I have 1997 es300 with 106k miles. Recently, the CEL & Trac off light came on. Went to Autozone, and the code is PO402. i am looking for advise on how to fix it. i appreciate any help.

lexusk8

From my ES repair manual, there is no such thing as a P0402 error code. Maybe you meant P0420. Are you sure you got the right code?

dan099

Lexusk8

yes,

Po402 (exhaust gas recirculation flow excessive detected)

thanx for the reply

4evDev

iTrader: (1)

I just had that same problem on my 93 SC 400, and it was a bad O2 sensor. I just took it to the Lexus dealership and they changed it - $450 CAD.

Heltah

Its not the o2 sensor!!!
The o2 sensor had absolutely nothing to do with the EGR system.
Be carefull about taking the advise of people who send their car to the dealership for everything.

This should help
http://www.obd-codes.com/trouble_cod...e-detected.php
Causes
A code P0402 most likely means one or more of the following has happened:

* The DPFE (differential pressure) sensor is faulty and needs to be replaced
* There is a blockage in the EGR (most likely carbon buildup)
* The EGR valve is faulty
* The EGR valve may not be opening due to a lack of vaccuum

This will affect your gas mileage and performance. Took me 5-10 minutes to change on another car

For all your obdii needs
http://www.obdii.com
http://www.obd-codes.com
http://www.obd-codes.com/trouble_codes/generic/

dan099

Thanks for the reply Heltah,

Is there a website or can you explain further "how to" to the solutions you suggested.

* The DPFE (differential pressure) sensor is faulty and needs to be replaced
* There is a blockage in the EGR (most likely carbon buildup)
* The EGR valve is faulty
* The EGR valve may not be opening due to a lack of vaccuum.

...and you mentioned you changed it in 5-10min. Changed what?

VVT-i

The 97 ES has two EGR designed. One which electric sensor on top of the EGR and another one is vacuum control. If you EGR has electric sensor that will most likely be the problem. You can check the EGR valve by apply vacuum at the EGR port( while the car at idle) , if the engine stall or die that mean the EGR is good.

dan099

VVT-i,

do you have a diagram or instructions showing how to check the EGR valve by apply vacuum at the EGR port( while the car at idle) , if the engine stall or die that mean the EGR is good.

Heltah

I cant find any diagrams for your car. It should show in the
owners manual, heres some general stuff
http://www.asashop.org/autoinc/dec97/egr.htm
http://www.fordscorpio.co.uk/egrsensors.htm
http://autorepair.about.com/od/gener...l/bldef165.htm
http://www.allpar.com/mopar/emissions.html

I would be willing to bet its the sensor, wether its electrical or vaccum. I assume
the vaccum ones fail more often as there are deposits running through the sensor and can build up.

What I would do, of course in order of price:

1 remove EGR valve, clean
2 If there are 2 vaccum hoses on the EGR valve. follow them remove and clean the DPF sensor and hoses.
3 re-install, run and observe

If the problem continues....
1 replace sensor electronic or vaccum.
2 Run and observe

If the problem continues......
1 replace EGR valve
2 run and observe

dan099

Hey Heltah,

Can you explain or show in pics how to :

1 remove EGR valve, clean
2 If there are 2 vaccum hoses on the EGR valve. follow them remove and clean the DPF sensor and hoses.
3 re-install, run and observe

hdygma

Dan099

Did you ever fix your 0402 problem? My research suggests it is either the ERG VSV or EGR position sensor (I know my ERG is closing).

Appreciate any help.

dan099

Hi Hdygma,

No I never did. I'm still looking for detailed instructions on how to fix.

stertan

guys. i just had this problem right now. I just got my is300 3 weeks ago (03 IS) 55000k . this is really annoying.