P0401 code

2001 MERCURY SABLE
164,000 MILES • 3.0L • 6 CYL • 2WD • AUTOMATIC
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ERIC FIELD
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OBD kicks 401 code. Hold hand near firewall on passenger side and can feel air blowing up. When driving sound is louder during acceleration. From inside sounds similar to something spraying. No fluid leaks.
May 13, 2021 at 9:33 AM
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KASEKENNY
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It does sound like you have a vacuum leak. So we are going to have to track this down.

Here is a guide that will help with this:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Below you will have the testing for this code if you want to run through that as well.

Let me know if you have questions. Thanks
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May 14, 2021 at 8:25 PM
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ERIC FIELD
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Thanks. Just seen your reply. Will get right on trying this.
May 15, 2021 at 11:26 AM
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KASEKENNY
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Sounds great. Let us know what you find with this and we can go from there. We will be here whenever you get to it. Thanks
May 16, 2021 at 5:14 PM
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ERIC FIELD
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After I removed the intake and throttle body was able to see this.
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May 21, 2021 at 8:49 AM
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KASEKENNY
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Oh my. I would say that is an issue. That appears that it was a DPFE at one point.

It has EGR lines running to both sides of it so that would explain where the air was coming from.

Please let us know if you need more info in the future. Thanks for the picture and using 2CarPros.
May 21, 2021 at 7:03 PM
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ERIC FIELD
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Since our last conversation I have replaced some bad pieces of vacuum line and the EGR valve. EGR Solenoid tested faulty so replaced that this morning. Cranked right up, but rough idle. As soon as I gave it some gas it shut off. Noticed that while engine was still cool (only ran for a minute) the exhaust tube from EGR valve was almost too hot to touch. Wondering if the DPFE could have been bad out of the box or another issue I haven't considered. Thanks in advance for any reply.
May 27, 2021 at 8:05 AM
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KASEKENNY
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It could but I would rule out base engine before condemning the DPFE again. Due to the EGR pulling exhaust gases, it is going to be the first thing that gets hot so I would expect it to be hot but it does sound quick.

Can you monitor the o2 sensor data when it is running poorly? Basically let's let it get up to temp and what the o2 sensor data and see if it compensates.

We need to monitor this and get a new post started as this as moved into a different issue as it is now running but running poorly. We just need to keep each post to one issue just so that others will find it if they have a similar issue.

https://www.2carpros.com/questions/new

Let's just check this info and get a new post started with it and we can figure this issue out. Thanks and sorry for any inconvenience.
May 28, 2021 at 7:02 PM