Nissan Sentra: P0400 EGR System malfunction

In this video I have a look at a Nissan Sentra that came in with some EGR trouble. It had a P0400 causing the engine light to come on. Pretty simple system so let’s have a look to see if we can fix it. -Enjoy!

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  1. Got to laugh a few times on this one. The crescent hammer we have all been there… and the schmoo spraying out of EGR when Eric gave it a blow.

  2. I thought stepper motors fail when hot. If so seems like an odd choice of actuators to use.

    Darnit…You got Gibbs in my eye! lol

  3. Yeah, besides the EGR, which is probably related anyways, I figured the converter was bad.
    I'm sure it's the cause of the previous engine failure, as is common to the 1.8L of that gen. Even some 2.5L in the Sentra and Altima as well.
    The converter literally crumbles and clogs the base of the vertical pipe exiting the cat housing. If that doesn't happen, the debris drifts to the rear converter and clogs it instead.
    this all causes a buildup of exhaust pressures and heat causing blown head gaskets and warped heads.
    On some of these the EGR system has been observed recycling the converter debris into the intake and making its way into the combustion chambers where it scores the cylinder walls and pistons.

  4. Eric, have you been on vacation? The reason I asked is that the first part of the video has excellent shots of your arms and I don't see any burn marks, cuts, skin graphs, third degree burns or any of the typical "tatoos" you normally have on your arms. Also, they looked unusually clean. I like the new title page format by the way. Guess it was time to change things up. How do you like the $700 Autel you're using in this video. I'm thinking of upgrading my DS708 for this MK808TS and was wondering what your opinion of this tool was. Denny

  5. Ever here of EGR code on a 07 maxima showing even tho it doesn’t have a egr? Very odd can’t find any info on Mitchell or alldata. Wilson from tool time was the best over the fence lol

  6. Yeah you fixed the EGR problem but for how long? I would have replaced the EGR without even messing with it. Especially if it was the original with all those miles on it or an unknown history with the engine replacement! Not worth my time even as a home mechanic to worry about it failing again. You gonna wash out the catalytic converter as well just as Scotty Kilmer does?

  7. Ewwwww… Panther pee in my face. Don’t use a paper towel to lean the lens!! It will put micro-scratches on it. Use lens cleaner solution and lens safe wipes. Paper towels will eventually cause the lens to start to fog up, and you can’t fix it. Also, if the lens has a coating, paper towels will tear it up. Not chewing on you, but about 6 years ago, I quite literally ruined a lens on my camera and got lectured about how not to clean a lens.

    The video was OUTSTANDING!! It’s too bad about the catalytic converter. Those things are so freakin’ expensive.

    Just wanted you to know, I enjoy your videos so much. Gosh, I never thought I’d become a fan boy, but…. too late. Keep up the great videos. I know it’s a pain to make, but mixed with your genius troubleshooting (Ivan would be proud) and great personality (SUGAR!!), it’s a perfect entertainment and teaching tool.

    Thanks so much!! You are the bestest!! (And, yes, in Texas, that’s a word!!) 😂😂

  8. Nice tear down and repair on the EGR. Very surprised it freed up and starting working. Curious though why you didn't remove the spring and clip on the pintle. The shaft and the guide it ran on could have been cleaned up more. I understand time is a factor, I would have liked to see the condition of it further.

  9. I'm thinking the faulty egr might have something to do with a crudded up converter ?? Maybe  I would throw a gallon of laquer thinner into the full fuel tank, and let it clear out the converter…..????  does that seem plausible ?????

  10. A new title for your skill set. EGR whisperer. Nicely done my friend. Too bad the converter has thrashed. As you noted probably costs more than the value of the vehicle. Damn shame.

  11. One for two! Nice Job! MAF sensor probably didn't help a borderline converter, so now it becomes how much does the customer like the car? COOL MR. O cup! Blowing through an EGR valve. I've done to an IAC, not to an EGR. Fun!

  12. Eric, @4:14 that ratchet is mighty close to the positive terminal of the battery. Yes, I do see the protective cover but good discipline can save your life – just ask a solider.

  13. I thought 'Oh god, he's going full Ivan' at 5 minutes into the video. Then I saw there was 20 more minutes and realized there has to be some bonus footage too then! I'll watch to the end but I'm pretty sure the transformation is complete.

  14. hi love the show , unless the coil is gone then the EGR value will work for the life of the car , you have too de-carbonize the egr regularly . with vauxhall's diesels they clog all the time

  15. Eric O and SMA go above and beyond yet again saving yet another customer some money by repairing, rather than replacing, yet another poorly designed expensive Nissan part. Friends don’t let friends buy Nissans but at least those who are stuck with one can benefit from SMA when your Nissan inevitably falls on its face as this one has done multiple times even on its second engine.

  16. Stuck EGR always gets fed carb cleaner first (1)…then you bang on it (2), then you take it apart (3), then you replace it (4). Unless you're making a video, then it's 3, 2, 1, 4 😉

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