370z engine blown
 

Hey guys, need some help. Took my car to nissan because engine was knocking. They said the engine was consuming oil which caused the piston rings to fry. So, turns out im getting a new motor. A few days later they call me and tell me the reason why my engine went out was because one of my Berk HFC's exploded which caused the engine to suck up the metal from the exhaust back to the engine. It's probably one of the craziest explanations ive ever heard. Is the even possible? Or are they full of ****? Theyre still covering the damages. Any suggestions?

No way. This sounds very much made up on Nissan's part.

:shakes head: :confused:

If this was the actual case & with the exhaust being aftermarket, then I am really surprised that they are covering it. I would think it was something else. You are pretty much getting a new car basically. What yr is your Z & how many miles did you have on the original motor?

sounds crazy. :confused:

yea, i don't know. It is pretty crazy. I've got an 09 with 43k. 6 speed. Has anyone heard of anything even close to this happening? Is it even theoretically possible? Why would they make up such an outrageous story? I'm just happy they're covering it, but i still feel a little weird.

A cat blowing up and sucking air in. Through the exhaust. Through closed valves. Which only let things out.

Do it with a little flair and show them the inside of your cat.

This HAS happened... but primarily in conjunction with pre-cats which are a catayltic converter attached to the exhaust manifold (built in) I've heard of it quite a few times...

Reason being is they are much closer to the exhaust ports on the block so they could more easily get particles sucked in by back pressure.

If they are warrantying it, then I wouldn't even bother arguing (but don't let them toss your cats). If they claim it is not going to be covered, then remove the cats and inspect them.

2009s and early 2010s are notorious for consumption issues so I wouldn't be surprised if they tried to pass the blame off.

My thought would be that if your cat material blew on your car long enough to cause damage and show noticeable oil consumption, you would also see increased emmisions or at the least, a strange exhaust note.

found this:

Catalytic converter damaging engine? - Nissanhelp.com Forums
blown motor/catalytic converter 2002 altima 2.5 - Nissan Forum - Nissan Enthusiast Forums

This is NOT the first time I heard of Berks F**king up cars but... that's a debate I won't even touch AGAIN! Lol.
Nissan is very fair with warranty coverage. Their motto is to have repeat customers. They offer me trade ins often and offer me full value or close to it for my cars. It may be done in hopes of you being a loyal nissan customer? Have you purchased other cars from them?

Disclaimer: its just something I noticed in my experience. This may NOT reflect everone elses experiences.

Wow! I've never heard of this. I was soon going to buy Berk HFC's but this has made me believe otherwise. Is it any HFC's or just the Berk that causes this?

Use to happen to the 02-06 Spec-V Sentras all the time on the Pre-Cats.

very glad that hasnt happened to mine yet... i got an 04 spec v with 140k on it haha

I've heard this A LOT! And mainly happened to Berk HFCs. I am from a G35 forum and that car has been around for a while that's why I heard this terrible story happened on G35 quite a lot of time. Just google it... On the other hand, I haven't heard Fast Intentions HFC had such a problem. I had them on my car and they were great. But don't count me on that tho...

I hope the Nissan dealership will be nice to you and cover all the cost for you!

WOW...... I have never heard this before either. I'm glad I did not order Berk.

Sorry, I have no faith in Berk. I consider them junk/trash parts, and wouldn't be a bit surprised by something they made failing. After the catback I bought from them and the lack of support for their poorly designed junk, I have nothing good to say.

-Rear hangers fall off the car/slide out of the grommets.
-Hangers when placed in the grommets are barely flush with the backs of them, and they are at an angle, so of course heat expansion/bumps will make it pull out as they are smooth, unlike the OEM design with the flange to keep this from happening.
-Berk told me they would send me a custom fabbed hanger which would allow the exhaust hanger to protrude further through the grommet. I was given a 2 week ETA about 2 months ago. Never saw it.
-Screw Berk. You want something that isn't junk? You're going to have to pay for it. I wish I had sacked up and spent a few hundred extra and gotten the NISMO CBE. Sounds great and doesn't fall off the damn car, and has a REAL warranty.


If there is valve overlap, then yes, it is possible that this occurred. Never buy Berk. /end rant.

Wow I've never actually heard such bad things about Berk. I guess I'll stay away just to be safe. Guess Fast Intentions is the best on the market right now. Blowing the engine is scary.

Surprised nissan is covering it!

Yep. I've heard this before. Either stay OEM or test pipes.

Woot, test pipes.

bingo!

^^^this. I owned an '02 and there was much drama about the precats being sucked back into the engine.

OP, at least the dealer is covering this under warranty.

wow, consider yourself lucky they aren't giving you **** and saying they aren't going to cover it

:iagree:, heard of this happening to a 350z, hfc manufacturer wasn't mentioned though. Makes me appreciate my mod selection even more, and i purchased from a mod friendly dealership. OEM for me for cats!

Another thing on Berk HFC I've heard a lot is the Service Engine Soon light comes on always. No big deal tho. But Fast Intentions has this "L" shaped non fouler makes the SES light off all the time.

Test pipe is good. But the only thing is you might have trouble to pass the inspection coz literally they are street illegal.

Does anyone else find it strange that Nissan apparently found that the aftermarket cats where the reason a several thousand dollar engine went boom and they are still gonna eat all that money?????????????? Something does not add up here, seems like the OP's mod according to Nissan directly resulted in the warranty issue.

I'm glad they're covering the damages. I spoke to berk about the cats, and they said that a cat failing is usually directly due to problems with the engine. I have no idea if this is true.

B.S. ! There is no possible way parts from the exhaust can be sucked into the engine thru the exhaust ports.

The engine is a simple pump and the exhaust can only pump pressure out, it can't work as a vacuum and suck particles back into it.

Dirt or foreign objects can only enter thru the intake or other sources, oil, broken internal parts, broken head gasket etc.

Back pressure is only a term used to describe the amount of restriction to exhaust flow caused by a internal muffler, baffle or cat etc. Back pressure does not mean a reverse flow of exhaust gases.

This guys example is a good reason to show why is better to keep the car stock, dealers and manufactures are always looking for reasons to deny a waranty claim if possible.

Just be glad they covered your repair under waranty.

Most likely the ring damage was caused by the rings never really seating properly or a excessivly lean air fuel mixture and even engine timing could do it or bad engine mapping

Exactly what i was thinking. Ive found with most brands, its better to just modify the catback if youre going to touch the exhaust and leave it alone there after. Its the one and only mod Ive done on my Z and it will remain that way until the warranty runs out. I dont have extra cash to replace the engine nor the legal help it would take to fight a warranty denial.

You know the exhaust ports stay open during the intake stroke, right? This is not a terribly uncommon occurrence (when cats go bad, that is)

Dealer can expense it back to Nissan, Nissan knows OC is an issue and doesn't ask questions.

Dealer wins loyalty at nissan's expense. A single engine cost is trivial to Nissan. Pretty straightforward.

Just went to the dealership to take a look at the broken HFC. The whole entire honey comb of the cat was broken off. It was just moving around freely. The tech at Nissan said "the only reason Nissan decided to replace the motor is because this motor is known for having oil consumption issues." I asked him if he was certain that the cat was the reason the engine failed..He said "it's one of the reasons.." I swear they'll never give you a for sure answer to anything. Should i go the test pipe route, have the hfc replaced (probably the worst idea since permanent viagra), or put the stock cats back on?

:iagree: Yezzzirrr. That's basically what I was saying earlier. Why lose a customer over a $9000 engine if he may buy a $40000+ car every 3 years or so?

There are only a couple of different cores being used.

Neither berk not FI make the cores, and it's worth checking into whether there is a material difference.

I am pretty sure the FI HFCs are 300 cell vs 200 for the berk.

:iagree: Yep, Nissan is full of shite.

Leave the cats stock. Just use a non-res exhaust. It will be the same difference in sound and hp. Either No resonators on the exhaust on a stock cat or test pipe on a resonated exhaust will still give similar gains. Unless you are changing everything from the intake, headers pipes and exhaust. The switcharoo won't make a big difference. The only true difference is forced induction.

It's not impossible that this happened, but the major damage was almost certainly due to inadequate lubing due to oil consumption.

To be fair, it can be difficult to figure out what caused what when two more more mechanical components fail at the same time -- all that matters is that they are covering it.

I'd look into a different set of HFC's or TP's.

exhaust valves are only open after the mixture has been ignited and the gases expelled out the exhaust after combustion, no air is ever sucked into the exhaust ports.

Vacuum is only created in the intake port , not the exhaust port

Cat material is fairly regularly sucked into the engine when they go bad. You should try searching these things before posting about them.

I think you misunderstand the way the valves are timed. Overlap is very common.

Indeed, especially with a high-revving NA motor. With boosted motors, overlap=power-loss and is kept to a minimum.

That's a really interesting idea -- I didn't think the resonators on an exhaust as restrictive at the core of a cat. If true, that's a good way to stay OEM and green, but pick up lost power. Would be neat to see a dyno comparison of the two set ups.