Engine Failed, CTSC Damaged

[NSXROC]

I would like to share an awful experience with everyone. At this time, I have many questions and I don’t have any answers to them. I would like to learn more about what might have happened and would really appreciate any help/comment.

Info of my car:

92 NSX
6-speed tranny with SOS short shift kit
Installed CTSC Autorotor at 70,000 miles (August 2006), current mileage 73,000
NEVER tracked the car, only for street use
HKS exhaust
K&N filer
RPS clutch
DEFI boost and fuel pressure gauges
All maintenance services up to date
May location – Seattle
Temperature – between 50 – 60F

What happened:

I drove my car out last Sunday afternoon to pick up a friend. I picked up my friend after 30 minutes of driving. Then, I entered the freeway again from a stop light. I speed up and watched the RPM reached 7500 with the first gear; I fast shifted to 2nd gear and watched the RPM hit 7000. Then, ALL HELL BROKE LOOSE!!!!!!!! I felt the engine stalled

I called a flatbed and had the car transported to a friend’s house before sending the car to my tech John at Zahntech the next day.

John inspected my car and found #5 and #6 cylinder piston disintegrated and the engine has a small crack (I noticed a pool of oil while the car stalled on the freeway). I am going to need a new motor. To make matter worse, we found that bits and pieces of the shattered pistons made their way through the intake and now my supercharger is also damaged.

I couldn’t sleep Sunday worrying. I couldn’t sleep yesterday after learning the damage. I don’t think I am going to sleep well tonight either not knowing what’s up with the supercharger.

It’s beyond frustration that this tragic incident happened. I did everything to ensure that a good mechanic worked on the CTSC install. The result from my dyno session was good (see pic)

The AF ratio was within CTSC specification. I didn’t even drive the car hard. I have only enjoyed the CTSC for 3,000 miles.

Zahnteh is doing the best he can right now working with a few people (including Autowave and Comptech) to try figuring out how to bring my car back to life again.

Questions:

What do you guys think it happened?

What else can I do to prevent detonation?

Have I not done enough to ensure proper preparation for CTSC?

Does any one know any low mileage (40,000 – 50,000 mi) motor for sale?


Please comment and if you would like to call me, I can be reached at (206) 228-5988.

Thanks in advance.

Donny

 

[Ponyboy]

Truly sorry about your incident. What do you mean by "disintegrating" pistons? Did John say anything about the bearings? Did you hear any knocking before the failure? However, we'll need a lot more information than this to diagnose. I'm sure Zahntech, Autowave, and Comptech will be able to figure out the problem.

Once that's identified, then you can take steps to mitigate it's occurance again.

I feel your pain. Engine failure has happened to me as well.:frown:

 

[Ponyboy]

FWIW, there are three NSX engines on eBay right now:

Engine 1

Engine 2

Engine 3

 

[scorp965]

Zahntech did the installation?

 

[NSXROC]

What do you mean by "disintegrating" pistons? Did John say anything about the bearings? Did you hear any knocking before the failure?

No, I didn't hear any "knocking". At high RPM, all I could hear was the high-pitch supercharger whine.

It's getting kind of techical for me. If John sees the post, perhaps, he will chime in.

 

[NSXROC]

FWIW, there are three NSX engines on eBay right now:

Engine 1

Engine 2

Engine 3

My car is 3.0L can't use 3.2L

 

[NSXROC]

Zahntech did the installation?

Yes, and his work was very good.

 

[Ponyboy]

My car is 3.0L can't use 3.2L

Plenty of owners have done the swap. Should I hear of some used 3.0L's out there, I'll post it up.

 

[WarpDriveKid]

Sorry to hear of your engines demise! Hopefully they will figure out exactly what was the cause, you can post and others will learn from this. Good luck and maybe an upgraded engine is in your future! :smile:

 

[nsxman2001]

FWIW, there are three NSX engines on eBay right now:

Engine 1

Engine 2

Engine 3

number 2 does not look like an nsx motor..more like a TL motors..probably a scam anyway..Sorry to hear about your damaged engine hopefully u will get rolling again soon.. Good luck

 

[The Kid]

Just curious, when was the timing belt done? Could it be possible?

 

[Hoover]

Any reputable performance engine builder will tell you exactly the cause of your engine failure upon inspection of the pieces.

If you know how to read the components, they tell a very long story.
Second, you will need to provide the builder with your spark plugs and a gasoline sample.

 

[NSXROC]

Just curious, when was the timing belt done? Could it be possible?

The timing belt was done 20k miles ago. i am not sure if it had something to do with it.

 

[NSXROC]

Any reputable performance engine builder will tell you exactly the cause of your engine failure upon inspection of the pieces.

If you know how to read the components, they tell a very long story.
Second, you will need to provide the builder with your spark plugs and a gasoline sample.

Thanks for the tip about the spark plugs and the gas sample. I will take that into consideration. I will know more when the engine is taken out of the car. Zahntech will then have a chance to inspect it further to determine the cause(s) of whole thing. Zahntech said the valves seem to be intact, but the pistons are destroyed. It's looking like a detonation issue at this time.

 

[AdvansCPAP]

Wow, sorry to hear what happened. Believe me, I know what it exactly feels like to have a motor go kaboom. I had a motor blow when I was running it hard and right when I hit redline..POW..oil light goes on and I could hear clunk clunk clunk..and see a trail of oil behind me. One of my rods snapped, spun around and busted a hole right through the block so hard the piece of the block put a dent on the inside of my hood (a civic on NOS).

The crack, if on your block, could be from a snapped rod or parts of the piston banging around inside the cylinder after it breaking causing the loss in oil. Now what caused it to happen. My guess is a lack of fuel resulting in a very lean condition and then detonation. It's too hard to hear detonation when you're going that fast with the engine and exhaust screaming away for most people.

If the cause was actually detonation, you would need to do the following to help prevent it:
Upgrade your fuel pump, add a new fuel filter, ditch the Comptech FMU for a better one, go with AEM EMS with wideband O2's, clean your old injectors or get new ones, get colder spark plugs and have it fine tuned on the street and on the dyno.

BTW how often do you hear about stock NA motors blow?..very rare..if they do, it's usually do to poor maintenance.

But hey, what do I know...it's just my wild guess.

 

[Elite]

How old was the gas that was in the car? The air/fuel in your tune looks good, but how aggressive is your timing?

 

[nsxotic911]

:frown: That sucks. My condolences to you.

Unfortunately, the weather around Seattle right now is cold, very cold. You have to be careful especially when at WOT.
The best way to detect/mitigate detonation, after a good tune, I think is with an A/F gauge and watch so it doesn't get lean.
I keep telling myself that it should be my #1 priority to buy one.. and this is another reminder.
Again, that sucks. Try to take a breather and forget about the pain....

 

[amo]

hi mate
shiiiit man sorry to hear
iv got a engine was thinkin of doin a rebuild and putting it in to mine
came out of a 91 with about 50k
but iam in the uk not usa

thx amo

 

[Hoover]

Thanks for the tip about the spark plugs and the gas sample. I will take that into consideration. I will know more when the engine is taken out of the car. Zahntech will then have a chance to inspect it further to determine the cause(s) of whole thing. Zahntech said the valves seem to be intact, but the pistons are destroyed. It's looking like a detonation issue at this time.

Next is "why" it detonated.

Regardless of what the dyno chart showed then, it's matter of what the problem is now.

The system you have is very simple, I've worked with quite a few of them. Check all the fueling components: Fuel filter, fuel pump, injectors (flow bench them) and voltage booster for you fuel pump. Then make sure it didn't overheat which also causes detonation. Check your thermostate, water pump etc...

You'll soon find the answer.

 

[J-RnsxT]

sorry to hear about your precious... are you running an engine management system? your temperature being cold 50-60F might have something to do leaning out your set up... im not expert when it comes to this but i made sure that my set up was below 12 on ARF... i think it you will benefit by putting 255lb fuel pump and bigger injectors...

 

[NSXROC]

hi mate
shiiiit man sorry to hear
iv got a engine was thinkin of doin a rebuild and putting it in to mine
came out of a 91 with about 50k
but iam in the uk not usa

thx amo

Amo, you got PM.

 

[J-RnsxT]

smn4nsx has engine and tranny for 5500

http://www.nsxprime.com/forums/showthread.php?t=92048

 

[NSXrunner]

Damn man, sorry to hear about your motor going boom. :frown: Its always on the back of my mind as to what to do heaven forbid if my car goes boom or if some random person forgets how to drive and hits my car. Do I have the patience to rebuild or just suck it up and work towards a replacement with another NSX or something else. Even though my car is strictly a weekend cruiser these days, I can't even imagine sitting and waiting for parts for potentially months on end if something goes wrong.

Hope things work out for you. :smile:

 

[titaniumdave]

My car is 3.0L can't use 3.2L

Parts are a direct bolt up if you do a whole long block.

What is up with the blower? Do you know if the blower has been 'over-boosting', does the Defi gauge have memory? Piston bits need to go through the valves to get back into the blower.

I would tend to not look at the Timing belt, unless it is broken. You will have bent valves if it skipped a tooth or slipped. You indicated the valves are OK.

 

[SaberX]

Donny - your story makes me feel sick... what a nightmare. I'm so sorry. Let me know if I can do anything to help. On a related note, in the colder weather I was able to confirm detonation with my CTSC. Please read this thread... everyone should read this thread!
http://www.nsxprime.com/forums/showthread.php?t=82726


Cliff notes:I have spoken to both Comptech and Shad about this issue. Comptech confirmed they are aware that the Autorotor is very sensitive to temperature and elevation changes. Meaning it makes more boost so easily and can lead to detonation under certain conditions. They said they are working on a "fix". I assume this means fixing the ACM to do the right thing when it sees cold temperatures. There was no ETA.

When I spoke to Shad, he confirmed my suspicions - as 1NSX2NV said in his post. Looks like this is clearly a relatively well known issue across the board. Hopefully Shad is working with Comptech on a fix.

In the mean time, I am always putting Lucas Oil octane booster in the car when I fill it up. I also made a change in the fuel pressure regulator as well ( bolt replacement) that basically allows fuel pressure to keep building on the rail. These are very "hack" interim fixes, but I have not heard any detonation since making these changes even in very cold weather (30deg). Hopefully the ACM fix will come soon.