16785/P0401/001025
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Revision as of 13:25, 11 June 2006 by Gerrit Speek (talk | contribs)
16785/P0401 - Exhaust Gas Recirculation Flow Insufficient Detected
Possible Symptoms
- Drivebility problems (check dtc's with Knock Sensor)
- Irregular behaviour
Possible Causes
- EGR valve stuck closed
- EGR valve leaks vacuum
- EGR flow restricted
- Circuit EGR short to B+
- EGR damaged
- Circuit DPF EGR sensor (differential pressure) disconnected, short to B+ or Ground
- DPF EGR sensor downstream hose off or plugded
- DPF EGR sensor damaged, wrong attached
- Control Module damaged
Possible Solutions
- Check all wiring and connections to and from EGR and DPF-EGR
- Check the EGR: use a vacuumpump and pull open the EGR: rpm should change
- Clean the EGR
- Check / Replace EGR
- Check / Replace DPF-EGR
Special Notes
- The EGR system is monitored when driving at steady state and the EGR is commanded on. When the DPF-EGR sensor indicates that EGR flow is less then a desired minimum a dtc is set.
- N.B. mechanics with less knowledge do exchange the EGR often, but 75% sure the problem will be back (probably the DPF-EGR sensor causes the problem).