Before reading further, please be advised that I am primarily making this post to gather competent opinions about the cause of my motor failure. I would really appreciate it if we could avoid turning this into a finger-pointing thread.

That being said, here is the abbreviated story:

My vehicle was the first G35 Coupe to be equipped with the STS Remote-mount turbo in May 2007. The installation was tuned to 356HP at 7PSI. The tune was competent and conservative, and served me well for 9 months.

In February 2008, the platform was significantly upgraded with a new larger intercooler and fast-spooling ball-bearing turbo. The installation was tuned to 370HP at 8PSI. (More on the details of the upgrade in a later post.) This tune was very conservative as well, and served me well for 2 weeks.

In March of 2008, my motor failed. The morning of the failure, my oil pressure read slightly lower than normal. The dipstick did not read anywhere near low levels, so I continued to drive the car normally. That same night, mid-drive on the way home, oil pressure dropped to zero, and the engine immediately started making a loud clunking sound that increased in frequency with increased RPM. I immediately pulled over. The engine was not leaking any fluids whatsoever. The engine continued to run, although with drastically decreased power. The next morning, I had the vehicle towed to my mechanic shop, during which the engine started up just fine to move the vehicle onto the truck and the lift.

Fast forward two weeks. The engine was pulled out, and shipped to GTM for analysis. The block had no holes, and there were no obvious sign of failure outside of the engine. Apparently, the inside is a completely different story. I was expecting a bent rod or damage more stereotypical of FI-related failure. But instead, this is what we found:

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It has been suggested that the result of this widespread damage might have been failure of the OEM Oil Pump. According to my brief research, no one has ever experienced this type of failure before. I am no expert on engine internals, which is why I am opening up this instance to the analysis of the more experienced members of this community.

I welcome your thoughts.

 

i cant believe you found a bunch of red X's in your motor...








good luck with the build, let us know if we can do anything for you. oil pressure is really tricky in these cars. not usually an issue with a stock motor but who knows when you have to pump oil soo far away from the engine.

 

i see some bold images

 

pics work for me... Although they are not fun to look at.

 

they work now for me

looks like typical oil starvation. the whole motor is ruined and you need to replace it. did you change the oil recently? switch types of oil?

 

as bearing clearances open up,oil pressure goes down.if you still had pressure before you tore the motor down it is probably not the pump.somewhere, somehow you started circulating junk though the motor.now you need to figure out what self destructed first and started that chain reaction.did you ever run low on oil?btwy that motor is wasted,sorry to see it

 

The motor is about 50,000mi old, and have been under FI for the last 10,000mi. I've been feeding it Amsoil or Mobile-1 10w40 for the last two years, with oild changes every 3,500mi or so. The motor has never had an oil consumption issue, and certainly never ran low on oil, to my knowledge.

 

After Sam took these pictures, I asked him to look at the OEM oil pump. I don't remember exactly what he said, but I believe he found something blocking one of the passages in the OEM oil pump. Perhaps he can chime in directly here.

Oil pressure was present before the motor was torn down, but only before it warmed up. After the motor warmed up to operating temps, oil pressure dropped to zero.

I assume that with such widespread damage, it is nearly futile to try to figure out the original cause of the failure?

 

did you drop the oil pan yourself? did you drain the oil before shipping it?

just wondering how much was in there...

basically three things could have happened...

you could have just had low oil pressure due to the fact it has to send it all the way to the back of the car to the turbo.

you could have hit something that caused an oil leak and ran the car low on oil.

or you could have gotten dirt, RTV, or some sort of junk in the pickup or through the bearings which would let less oil flow through the oil passages and cause it to have low pressure and less flow, causing everything to heat up and ruin every bearing/rotating part...

not ruling out the oil pump but we have done well over 100 stock motor FI VQs in the past year and havent seen one fail...

good luck with your new build. i am sure you are in good hands.

 

So you continued to let your car run while the oil pressure read 0?

Sorry to hear about that

 

There are athor cars with the kit that have over 25K+ miles and so far no problem. If you look at it, the way the oil line is tapped from the Oil Filter going to the turbo isn't much of a distance compared to other Front Mount Turbo. I don't think there is any added resistance since the turbo and the Oil filter is pretty much in the same level so flow shouldn't be that bad. I'm also curious why did the OEM pump fail or if it is even the culprit.

Goose,
I know what you have been through and all the $$$$$$$ you have to shell out this past month. To bad you didn't get to enjoy your upgraded kit that much.

 

Some food for thought and history on this car..

We did this car as the first STS turbod car in the North East last summer.

Car ran fine for well over 9 months

Customer decided to upgrade the turbo and retune with another shop in CT area

2 weeks following the upgrade the motor blows

Now based on the pictureds shown it looks like one or more of the bearings had went and sent contaminants into the rest of the motor and made its way all the way up to the cam journals, wiping them out..

It could have been caused by a contaminant introduced when the new turbo was installed.

It could have been caused by low oil level after the install

It could have been caused by over reving the engine

However without seeing the tops of the rod bearings, and signs of ptting from obvious detonation, one could conclude that detonation was most likely not the culprit.


The oil pressure upon intital start up and then reducing as the engine oil warmed up, tells a tale of incresed bearing clearances as the engine warmed up..

IMHO most likely NOT an oil PUMP failure.

 

Yep. I went a short distance to get off the Brooklyn Queens Expressway. It's an elevated highway with absolutely no shoulder. That's the last place in the world I would ever want to be stuck, for personal safety reasons.

 

Julian,

Many thanks for the input. I tend to agree with your final conclusion on this. No one has ever seen an OEM Oil pump go bad, and I doubt I am so special to be the only exception.

As you know, I'm also been pretty careful and conservative with the vehicle, so I can rule out low oil negligence and over-revving. Also, my priorities have also been conservative tuning for longevity, and I've never really cared for pushing the utmost limits of HP-TQ numbers.

I believe Sam commented that there was a good amount of carbon with no obvious signs of detonation, but perhaps he can take some more detailed pictures to highlight the areas you mentioned.

 

my vote as well

 

*edit

 

No worries about the OT, but I'm pushing this answer the other thread here.

 

Well, I have

 

Damn. What happened there?

 

I happened there... 7800rpms, + 6500 RPM launch control..