P0401 is a usual OBDII trouble code that’ll pop up in the Ford Explorer. It needs to do with the emissions system and stands for:

P0401: EGR → insufficient Flow

The EGR system on a vehicle is responsible because that recirculating exhaust gasses in stimulate to lower the vehicles emissions output. There are three key parts that the Explorer’s EGR system. They are the EGR Valve, Differential pressure Sensor, and also the Actuator Solenoid.

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P0401 is a general code, which method that regardless of the year (1996+ anyway) and also the model, it’ll have actually the same definition regardless of i m sorry manufacturer constructed the automobile (Ford explorer or not).

Related: P0420 Ford Explorer

Ford traveler P0401 Symptoms

Most of the time there are not walking to be symptoms when P0401 is triggered, various other than the organization engine quickly light itself. In some too much cases, girlfriend may notification a slim ping or knock.

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Service Engine shortly Light– P0401 will certainly illuminate the company engine soon light. Knocking Sound– In specific cases, there might be a noticeable knock that comes from the vehicle. It’ll sound virtually like piston slap.


P0401 Causes: Ford Explorer

Diagnosing what is leading to the P0401 password in the traveler is typically not really tricky. Below are the most typical causes:

Blocked EGR Tube– The tube the carries the exhaust gases back to the motor may clog up end time. Alternatively, it can come to be bent or kinked. This is particularly true if you room experiencing P0401 best after doing some engine work. Inspect the tube and also see if the is cracked, clogged or otherwise damaged. EGR Valve chin is Bad– The EGR valve chin is commonly not walk to it is in the ar to start. But, they absolutely are the reason of P0401 frequently enough. Vacuum Issues– The EGR valve counts on engine vacuum to operate. So, if you room encountering P0401 and other codes, the P0401 might be a symptom of bigger problems. Because that instance, if the engine is no running well sufficient to produce sufficient vacuum to operate the EGR valve, than P0401 will often be thrown. Sensor Issue– The Differential push Feedback- EGR sensor deserve to go faulty and cause the EGR valve to stop operating properly and also throw the code.

Explorer P0401 Fix

The an excellent news with P0401 is the it rarely ever expenses much money to fix, and also it is typically pretty simple to gain the problem, since it is ideal on height of the engine. Many folks view P0401 inadequate EGR flow, look up the price of one EGR valve, see exactly how cheap that is and also just litter a new one on.

That deserve to be a mistake. That’s since the EGR valve is not constantly going to it is in the culprit. Here are some of the most common fixes to assist clear the P0401:

check the EGR Tube- It’s a good idea to inspect the pipe going to the EGR due to the fact that it’s often the cause of P0401, simple to do, fast, and replacing the is very affordable. If it’s cracked, you’ll require to get a new one. If it’s clogged girlfriend can acquire away with cleaning it and replacing it.


Testing her EGR mechanism is reasonably easy to do. The most an overwhelming aspect is the DPFE sensor. If you aren’t sure you have the right to tackle that, girlfriend can always test everything else first. By process of elimination, you deserve to be relatively confident the the DPFE is at fault. If there is anything you would like to add about P0401, please feel cost-free to add a comment below. Great luck!!