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P0401 Diagnostic Trouble Code Discussion for September 2011

Insufficient EGR Flow Detected


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Trouble Ticket Help Requests for DTC P0401
Help Request Posted
2003 Ford F-450 Super Duty XL 6.0L No Start VIN: 1FDXF46P93
P0401: Insufficient EGR Flow Detected. I have a strange one here. Thought it was a normal 6.0 no start. I have 150 PSI of high oil pressure, but my IPR is at 0%. I can command my IPR to 90% and it builds 4000psi but still doesnt start. I dont know where to start on this. Anyone ever run into a prob...
September 07, 2011
2001 Toyota Tacoma DLX 2.7L Poor Idle Quality, High Idle VIN: 5TEPM62N41
P0401: EGR System Insufficient Flow Detected. Your help would be greatly appreciated on this Toyota. When it first came to us, it was idling so high it was hitting rev limiter and surging up & down. We initially removed Throttle position sensor & ensured it had been installed properly. Smoke teste...
September 14, 2011
1999 Toyota Camry LE 2.2L MIL Lamp on VIN: 4T1BG22K8X
P0401: EGR System Insufficient Flow Detected. Tested and found bad vacuum switch for egr car left back four days later.Retested circuit noticed with test light on ground side of connector and vacuum gauge hooked to egr side of switch command with scanner test light will flash and vacuum will bleead off sl...
September 19, 2011
2003 Acura MDX 3.5L Misfire, MIL Lamp on VIN: 2HNYD18693
P0401: EGR System Insufficient Flow Detected. Replace engine with used (see repair history). All went well, first road test the vehicle ran great. Performed alignment, road tested again to check steering wheel centering, vehicle misfired, code P0304 - found #4 coil was no good, swapped it out, road tested...
September 23, 2011
2000 Ford Expedition XLT 4.6L Poor Idle Quality, MIL Lamp on VIN: 1FMRU1664Y
P0401: exhaust gas recirculation flow insufficent. poor idle quality with P0401 code. cleaned EGR system, cleaned IAC valve, cleaned TB, triple checked EGR system vaccum routing. Live data shows that all the O2 sensors are extremly lazy. O2 sensors will show appx 0.030v and switch to 0.040 very slowly and some...
September 25, 2011
2000 Ford Expedition XLT 4.6L Poor Idle Quality, MIL Lamp on VIN: 1FMRU1664Y
P0401: exhaust gas recirculation flow insufficent. poor idle quality with P0401 code. cleaned EGR system, cleaned IAC valve, cleaned TB, triple checked EGR system vaccum routing. Live data shows that all the O2 sensors are extremly lazy. O2 sensors will show appx 0.030v and switch to 0.040 very slowly and some...
September 26, 2011
2004 Ford Freestar 3.9L Stall VIN: 2FMZA50664
P0401: Insufficient EGR Flow Detected (ESM System). ... just off or at idle. In addition it will act at highway speed as if the ignition was cycled off resulting in a hard jerk.It will also stall at low speed(20mph). Restart may require up to 10-15 seconds of cranking to restart. This occurs only intermittently...
September 27, 2011
2003 Ford F-450 Super Duty XL 6.0L No Start VIN: 1FDXF46P93
P0401: Insufficient EGR Flow Detected. I have a strange one here. Thought it was a normal 6.0 no start. I have 150 PSI of high oil pressure, but my IPR is at 0%. I can command my IPR to 90% and it builds 4000psi but still doesnt start. I dont know where to start on this. Anyone ever run into a prob...
September 07, 2011
2001 Toyota Tacoma DLX 2.7L Poor Idle Quality, High Idle VIN: 5TEPM62N41
P0401: EGR System Insufficient Flow Detected. Your help would be greatly appreciated on this Toyota. When it first came to us, it was idling so high it was hitting rev limiter and surging up & down. We initially removed Throttle position sensor & ensured it had been installed properly. Smoke teste...
September 14, 2011
1999 Toyota Camry LE 2.2L MIL Lamp on VIN: 4T1BG22K8X
P0401: EGR System Insufficient Flow Detected. Tested and found bad vacuum switch for egr car left back four days later.Retested circuit noticed with test light on ground side of connector and vacuum gauge hooked to egr side of switch command with scanner test light will flash and vacuum will bleead off sl...
September 19, 2011
2003 Acura MDX 3.5L Misfire, MIL Lamp on VIN: 2HNYD18693
P0401: EGR System Insufficient Flow Detected. Replace engine with used (see repair history). All went well, first road test the vehicle ran great. Performed alignment, road tested again to check steering wheel centering, vehicle misfired, code P0304 - found #4 coil was no good, swapped it out, road tested...
September 23, 2011
2000 Ford Expedition XLT 4.6L Poor Idle Quality, MIL Lamp on VIN: 1FMRU1664Y
P0401: exhaust gas recirculation flow insufficent. poor idle quality with P0401 code. cleaned EGR system, cleaned IAC valve, cleaned TB, triple checked EGR system vaccum routing. Live data shows that all the O2 sensors are extremly lazy. O2 sensors will show appx 0.030v and switch to 0.040 very slowly and some...
September 25, 2011
2000 Ford Expedition XLT 4.6L Poor Idle Quality, MIL Lamp on VIN: 1FMRU1664Y
P0401: exhaust gas recirculation flow insufficent. poor idle quality with P0401 code. cleaned EGR system, cleaned IAC valve, cleaned TB, triple checked EGR system vaccum routing. Live data shows that all the O2 sensors are extremly lazy. O2 sensors will show appx 0.030v and switch to 0.040 very slowly and some...
September 26, 2011
2004 Ford Freestar 3.9L Stall VIN: 2FMZA50664
P0401: Insufficient EGR Flow Detected (ESM System). ... just off or at idle. In addition it will act at highway speed as if the ignition was cycled off resulting in a hard jerk.It will also stall at low speed(20mph). Restart may require up to 10-15 seconds of cranking to restart. This occurs only intermittently...
September 27, 2011