Hi All
Just thought I would share my experience finally rectifying the dreaded P0402 (EGR excessive flow) error on the wife’s 08 500 1.3D Multi.
The P0402 error started to appear intermittently about 6 months ago, after a code reset, it would sometimes be fine from anywhere between a few days to a few weeks before coming back (and going into limp home mode).
During the course of the issue, I did the following - in chronological order
1) Replaced MAP sensor – No Joy.
2) Replaced DPFE Sensor – No Joy.
3) Removed EGR solenoid and worked the valve – As described in post on this forum. – No Joy
4) Removed and cleaned the EGR valve and checked for blocked passageways etc. – None found and was in relatively clean condition – This procedure is an absolute Nightmare, so not recommend for the faint of heart.
After all the above and many hours of wasted time, the code STILL appeared.
One thing I did not check and turned out to be the cause of the intermittent fault, was the pipe from the exhaust to the DPFE sensor…. It was clogged with carbon at the exhaust end of the pipe, restricting flow to the DPFE sensor. Why I did not check this first, God only knows, as it is far easier to fix than any of the above.
Anyway, it has been fine now for several months, and I just wanted to post on here to maybe help someone who gets the P0402 code and was thinking about changing all the bits as described. As failure of any of the parts listed can potentially cause the issue, I learnt the hard way and it would be worth checking the exhaust to DPFE sensor pipe FIRST – before embarking on a crusade.
Just thought I would share my experience finally rectifying the dreaded P0402 (EGR excessive flow) error on the wife’s 08 500 1.3D Multi.
The P0402 error started to appear intermittently about 6 months ago, after a code reset, it would sometimes be fine from anywhere between a few days to a few weeks before coming back (and going into limp home mode).
During the course of the issue, I did the following - in chronological order
1) Replaced MAP sensor – No Joy.
2) Replaced DPFE Sensor – No Joy.
3) Removed EGR solenoid and worked the valve – As described in post on this forum. – No Joy
4) Removed and cleaned the EGR valve and checked for blocked passageways etc. – None found and was in relatively clean condition – This procedure is an absolute Nightmare, so not recommend for the faint of heart.
After all the above and many hours of wasted time, the code STILL appeared.
One thing I did not check and turned out to be the cause of the intermittent fault, was the pipe from the exhaust to the DPFE sensor…. It was clogged with carbon at the exhaust end of the pipe, restricting flow to the DPFE sensor. Why I did not check this first, God only knows, as it is far easier to fix than any of the above.
Anyway, it has been fine now for several months, and I just wanted to post on here to maybe help someone who gets the P0402 code and was thinking about changing all the bits as described. As failure of any of the parts listed can potentially cause the issue, I learnt the hard way and it would be worth checking the exhaust to DPFE sensor pipe FIRST – before embarking on a crusade.
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