[stable rock]

Hi Firends,

The check engine light in my car is glowing and when scanned got an error code 0402 (Excessive air flow in EGR). Other symptons are black smoke when at sudden acceleration/ high RPM. Pick up is also less. The A.S.S asked me to change the EGR without even checking the EGR unit. What will be the cause for this. Please suggest a good mechanic or workshop in Bangalore to rectify this.

Vehicle Details -2005 Hyundai Elantra CRDI.
Odo Reading - 2,17,000 kms.

Regards,
SR

[Zappo]

Has the ASS checked the Differential Pressure Sensor? If not please ask them to check the voltage on the sensor both at idle and when the EGR is open. In my opinion, the sensor has a bigger chance of failure than the EGR valve itself.

[Jeroen]

Originally Posted by Zappo

Has the ASS checked the Differential Pressure Sensor? If not please ask them to check the voltage on the sensor both at idle and when the EGR is open. In my opinion, the sensor has a bigger chance of failure than the EGR valve itself.

I would agree a few more checks need to be done, before starting to swap parts. Easy enough just google Hyundai Elantra error code 402

Here is the result:

http://repairpal.com/OBD-II-Code-P0402

Note that this site also lists the "common misdiagnoses" one of which is the EGR valve!!!

Jeroen

[rocky080]

Originally Posted by stable rock

Hi Firends,

The check engine light in my car is glowing and when scanned got an error code 0402 (Excessive air flow in EGR). Other symptons are black smoke when at sudden acceleration/ high RPM. Pick up is also less. The A.S.S asked me to change the EGR without even checking the EGR unit. What will be the cause for this. Please suggest a good mechanic or workshop in Bangalore to rectify this.

Vehicle Details -2005 Hyundai Elantra CRDI.
Odo Reading - 2,17,000 kms.

Regards,
SR

Are you running any performance mods like K&N/green cotton filter or tuning boxes? and does your engine RPM get stuck at a particular RPM while accelerating.

[stable rock]

Originally Posted by rocky080

Are you running any performance mods like K&N/green cotton filter or tuning boxes? and does your engine RPM get stuck at a particular RPM while accelerating.

Hi Rocky,

I have not done any modifications. Car is in stock condition. RPM is not getting stuck too. Only excessive black smoke during acceleration.

@Zappo - Is Differential Pressure Sensor same as Mass Air Flow Sensor.

Please suggest a good mechanic or workshop in Bangalore to check this.

Regards,
SR

[rangakishen]

Originally Posted by stable rock

Please suggest a good mechanic or workshop in Bangalore to check this.

I would suggest going to any Bosch Service center close to your area. In my experience they are quite straight forward and well versed with cars from many manufacturers.

[rocky080]

Originally Posted by stable rock

Hi Rocky,

I have not done any modifications. Car is in stock condition. RPM is not getting stuck too. Only excessive black smoke during acceleration.

@Zappo - Is Differential Pressure Sensor same as Mass Air Flow Sensor.

Please suggest a good mechanic or workshop in Bangalore to check this.

Regards,
SR

Hi Stable rock

I asked the same cause I had the same error code issue on my elantra when my MAF sensor and performance filter were chocked. But the only difference was that my engine RPM used to get locked at a particular RPM while revving. This issue got sorted out after cleaning the MAF sensor. There are multiple reasons for black smoke and lack of pick up, my suggestion would be to:

1.Change the air filter and get the egr valve along with MAF sensor cleaned at the A.S.S(Please supervise the work being done)
2. While at it check if there is excessive oil in the pipe that connects beyond the MAF sensor.
3. Get your Intercooler plumbing checked for cracks or leaks in all the joints.
4. Check if there is excess oil in the inter cooler.

Please report you findings after this, if the A.S.S refuse to check this and maintain the egr valve has to be changed, then take a writing from them that they will refund the amount if issue fails to get fixed before replacing the part.