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P0401 Diagnostic Trouble Code Discussion for September 2004

Insufficient EGR Flow Detected


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Trouble Ticket Help Requests for DTC P0401
Help Request Posted
1996 Chevrolet Corsica 3.1L MIL Lamp on, comes back on VIN: 1G1LD55M4T
P0401: Insufficient EGR Flow Detected. on this vehicle we have replaced the MAP sensor and the EGR everything else has tested good on this vehicle but the code keeps on coming back.
September 07, 2004
1996 Toyota Previa DX 2.4L MIL Lamp on VIN: JT3GK12M3T
P0401: EGR System Insufficient Flow Detected. Van runs good cannot hear any vacumn leaks.Drove van with cover off of engine and could see egr valve working. Already changed vapor canister at custermer request. dealer said it was bad. I have a 25860-75070 vacumn valve for the vapor canister but I do not th...
September 07, 2004
1996 Chevrolet Corsica 3.1L MIL Lamp on, comes back on VIN: 1G1LD55M4T
P0401: Insufficient EGR Flow Detected. on this vehicle we have replaced the MAP sensor and the EGR everything else has tested good on this vehicle but the code keeps on coming back.
September 08, 2004
2001 Isuzu Rodeo LS 3.2L MIL Lamp on VIN: 4S2DM58W01
P0401: Insufficient EGR System Flow Detected. Vehicle keeps setting code P0401- no driveability problem. Searching the archives found one match concerning plugged EGR pipe in the intake manifold.I cleaned this one with carb cleaner and a coathanger, removed the EGR valve to check both exhaust and intake s...
September 09, 2004
2001 Toyota Camry CE 2.2L MIL Lamp on VIN: 4T1BG22K11
P0401: EGR System Insufficient Flow Detected. Car came in 57,000 miles p0401. replaced egr transducer/modulator and egr valve as usual. The vaccum switching valve checked out fine, car came back 21 days later, 1,200 miles more, same code. Checked system complete and it was all good. Vaccum signal to egr t...
September 09, 2004
1998 Ford Escort SE 2.0L MIL Lamp on VIN: 1FAFP13P0W
P0401: egr flow insufficient. This Escort belongs to another tech at our dealership. MIL on occasionally and PO401, insuficient egr flow, is stored. It will go-out soon, and it might be a week or a month before it is set again. No driveability problems or pinging occurs. Do we need to repl...
September 15, 2004
2000 Toyota Camry CE 2.2L MIL Lamp on VIN: 4T1BG22K3Y
P0401: EGR System Insufficient Flow Detected. I am having problems with this one I have tried to understand the way the EGR works in this car. I know that the ECU knows the EGR is working, by the map sensor voltage change. My qustion is how much of a voltage change does it have to see. My problem is that ...
September 20, 2004
1995 GMC Sonoma SL 4.3L MIL Lamp on VIN: 56S8512738
P0401: Insuficient EGR flow detected. This truck came to me with the mil on and the three codes mentioned. When I clear the codes it can take as much as 500 miles for the mil to come back on. The owner has no drivabillity complaints. Yesterday I peeled the insulation back from the main wire harnes...
September 29, 2004
1996 Chevrolet Corsica 3.1L MIL Lamp on, comes back on VIN: 1G1LD55M4T
P0401: Insufficient EGR Flow Detected. on this vehicle we have replaced the MAP sensor and the EGR everything else has tested good on this vehicle but the code keeps on coming back.
September 07, 2004
1996 Toyota Previa DX 2.4L MIL Lamp on VIN: JT3GK12M3T
P0401: EGR System Insufficient Flow Detected. Van runs good cannot hear any vacumn leaks.Drove van with cover off of engine and could see egr valve working. Already changed vapor canister at custermer request. dealer said it was bad. I have a 25860-75070 vacumn valve for the vapor canister but I do not th...
September 07, 2004
1996 Chevrolet Corsica 3.1L MIL Lamp on, comes back on VIN: 1G1LD55M4T
P0401: Insufficient EGR Flow Detected. on this vehicle we have replaced the MAP sensor and the EGR everything else has tested good on this vehicle but the code keeps on coming back.
September 08, 2004
2001 Isuzu Rodeo LS 3.2L MIL Lamp on VIN: 4S2DM58W01
P0401: Insufficient EGR System Flow Detected. Vehicle keeps setting code P0401- no driveability problem. Searching the archives found one match concerning plugged EGR pipe in the intake manifold.I cleaned this one with carb cleaner and a coathanger, removed the EGR valve to check both exhaust and intake s...
September 09, 2004
2001 Toyota Camry CE 2.2L MIL Lamp on VIN: 4T1BG22K11
P0401: EGR System Insufficient Flow Detected. Car came in 57,000 miles p0401. replaced egr transducer/modulator and egr valve as usual. The vaccum switching valve checked out fine, car came back 21 days later, 1,200 miles more, same code. Checked system complete and it was all good. Vaccum signal to egr t...
September 09, 2004
1998 Ford Escort SE 2.0L MIL Lamp on VIN: 1FAFP13P0W
P0401: egr flow insufficient. This Escort belongs to another tech at our dealership. MIL on occasionally and PO401, insuficient egr flow, is stored. It will go-out soon, and it might be a week or a month before it is set again. No driveability problems or pinging occurs. Do we need to repl...
September 15, 2004
2000 Toyota Camry CE 2.2L MIL Lamp on VIN: 4T1BG22K3Y
P0401: EGR System Insufficient Flow Detected. I am having problems with this one I have tried to understand the way the EGR works in this car. I know that the ECU knows the EGR is working, by the map sensor voltage change. My qustion is how much of a voltage change does it have to see. My problem is that ...
September 20, 2004
1995 GMC Sonoma SL 4.3L MIL Lamp on VIN: 56S8512738
P0401: Insuficient EGR flow detected. This truck came to me with the mil on and the three codes mentioned. When I clear the codes it can take as much as 500 miles for the mil to come back on. The owner has no drivabillity complaints. Yesterday I peeled the insulation back from the main wire harnes...
September 29, 2004