Please Help - Engine knock and then fail

Looking for some advice if anyone can help. I have a 2019 Infiniti QX50 with 20,829 miles on it. I was driving home yesterday with my wife and son and heard what sounded like a faint clanging come from the engine. It was barely audible and I had to turn down the radio and really focus to hear it. I immediately while in the car had my wife contact Infiniti for an appointment. No sooner did she hang up did the sound become very loud and I felt like I was loosing power in the accelerator - so I immediately pulled over and called for a tow as soon as there was a safe shoulder to park on the highway.

The tow driver tried to turn the car on but it wouldnā€™t even turn on at that point. They brought the car to my home and my fatherā€™s diagnostic reader showed the codes below.

Is this essentially a complete engine failure and total replacement? Is it very serious?

Iā€™m also concerned because some friends said donā€™t tell the dealer you drove after hearing the sound they may void the warranty. But what was I supposed to do just stop in the middle lane of a highway with my wife and 4 year old in the car rather then get over to the shoulder? Would the dealer really void the warranty for that? If so how on earth should I explain it to not void the warranty ?

P23F5
Cylinder 4 Injector ā€œBā€ Air-Fuel Ratio
Imbalance

P0304
Cylinder 4 Misfire Detected

P0303
Cylinder 3 Misfire Detected

P0014
ā€œBā€ Camshaft Position - Timing Over-Advanced or System Performance Bank 1

P11A7
Indicates a problem with the VCR stopper position.

Those codes may or may not imply the engine is toast. Only an experienced mechanic inspecting the engine can tell you that. But it sounds like there indeed was a major problem. What is the engine oil level on the dipstick?

Suggest to tell the dealership you stopped driving and turned the engine off as soon as it was safe to do so. Presuming this is an accurate statement.

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If itā€™s under warranty, tow it to the dealer. If not, Iā€™d still rather have the dealer diagnosis. Ya donā€™t have to put a sign in the car that you drove it 20 miles. You pulled over as soon as you could.

Who knows what the knock was? If the engine seized, thatā€™s not a good sign. Did you check for oil?

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Thanks George - the statement is in fact true. Unless I stopped in the actual line of the highway that would be the only way I could have stopped sooner. I only drove until I was able to get to a portion of the highway that had a shoulder on it or exit and the shoulder came first so I pulled over the moment I saw it. Time from hearing the initial sound to being pulled over way 5-7 minutes tops. Iā€™m concerned the dealer would still void my warranty for saying that (which is the truth).

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Letā€™s see?

Variable Compression Ratio engine with Variable Valve Timing.

What could go wrong?

Tester

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Thanks bing - I just wanted to be honest and say the truth because I fear they may say no way with this damage did you stop instantly - and I didnā€™t because I couldnā€™t. I drove maybe 1.5 miles tops until I was able to get to a shoulder to pull over safely on.

When I pulled over I turned the engine off. The tow driver turned it on but it sounded like a really rough start. It would only move in drive - not reverse. And it was struggling to even move in drive per the tow the driver.

My engine oil is fine; the car itself says 3,500 miles until next change and no oil light (even now) was present. I supposed I could top it off before I have it towed to the dealer tmrw just to ā€œsafeā€.

When was the last time you checked the oil level? When was the last oil change. If the oil level was low the damage is on your dime

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My last oil change as a year ago next week. When my oil was changed last I was 17,372 miles. The cars current mileage is 20,829 and no oil light was ever on.

There may be a requirement the owner do a visual check of the engineā€™s dipstick. Donā€™t know. But it probably makes sense for you to do that so youā€™ll be able to say. Do you know how to check the dipstick? If not Google should provide a vdo.

I just checked it. It is dark in color and on the lower end of the stick but not yet at the ā€œlow markingā€. I would say itā€™s about an inch above the low marker.

I can add some more in tonight to be safe.

Ok, the oil level is correct. The engine started to fail at a VERY low mileage. You pulled the car over in the first SAFE space you found.

You have nothing to worry about. Nissan does.

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Tell them what @mustangman said and donā€™t add any information. If you provide more information they may have more reason to deny the claim. IMO the misfires may be due to the air/fuel imbalance.

BTW, any discussion we have here is for you to understand better what is going on. Donā€™t repeat it to the dealer. They are capable of diagnosing the problems themselves. As I mentioned above, anything you say can and will be used against you.

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And it has a 6 year/70,0000 powertrain warranty which definitely applies. If the dealer tries to say no, escalate it using the contact info in your owners manual.

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Thank you I plan on doing exactly that. I appreciate the information!

Would you mention the article that Tester provided above?

You can, but it was from last December, and they could say ā€˜itā€™s out of dateā€™, even though itā€™s not.

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The dealer is well aware of potential failures and they will not be interested in an article in a publication. The plot thickens as they say. Main bearings, metal shaving in the pan? I suspect the first thing theyll do is try to turn it over by hand. Then when it doesnā€™t move, pull the pan and check the bearings and look for metal shavings. Might want to ask for a loaner.

Iā€™m going to ask for one. My main fear is the dealer trying to turn the blame on me for this with some ā€œloopholeā€ like oh yes even though we say every 7,500 miles to change the oil and itā€™s only been 4,100 and even though you didnā€™t have an oil light or check engine light you should still change the oil every 12 months and itā€™s been 14 so itā€™s your fault. Or something along those lines.

I just fear any costly repair their instinct will be to try and get out of covering it and somehow blame me.

If they give tou any push back, yes I would mention it.

Engines are not supposed to fail that early.

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And get everything in writing

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