Hello all. I am hoping to get some help in the right direction to find out what's exactly wrong in order for me to make the correct repairs.

Car is a 02 z06, just went over 50k miles. Has k&n intake and the rest is stock with the motor.

I was WOT in 4th gear at around 5200rpm, i felt a slight buck(like a fuel cut/boost cut) and I let off the throttle. Slowed down into turn one and the power kept on dropping. The car lost power and did not start again.

It threw 3 codes from the pcm after this happened.

p0101
p1514
p0343

I was at the track when this happened, 4-5 hours away from home. So, for what it was worth, I cleaned the MAF sensor and put it back on with no luck. It wasn't dirty at all.

The next day, I was able to purchase a new cmp sensor and replaced it. Again, no luck. I was lucky to run into another corvette owner, only to find out at the end he is on the forum, and he helped me determine that I have spark. The plug pulled from cyl. 1 was dry. Tested for fuel pressure by pressing on the schrader valve and fuel leaked out. I bought a fuel pressure gauge and going to test the actual fuel pressure today.

Before the the engine died, I had two codes pop up in the previous session.

c1293(does it at least once at the track, so i just pit in and restart the car)

p1575, never had this pop on before.

There was no bang, explosion, or smoke when it happened. At least the engine oil level is still good.

From what I've read online so far, i may have a snapped timing chain or it may have skipped a tooth. I don't think my cam bolts backed out, as I read a few people with cam upgrades had those issues and i haven't thouched that.

If my suspicions are correct, is there a way to diagnose the timing chain without taking everything apart? Or is there another thing that could've caused this issue?

Rob, if you're reading this post, I wanted to thank you again for your help at the track. I feel lucky to have ran into you there. I will see you soon at the track again.

 

I should've noted the springs have been replaced already. Thank you!

 

Hmmm, I thought the 0343 code was for a cam shaft position sensor, which I replaced. For what it's worth, I see the rpms go up 100-200rpms when I try to start the car. Doesnt that mean the crank shaft sensor is working?

Thanks.

 

I might as well check the springs as I will most likely be tearing it down to inspect the timing chain. I guess this is the perfect time to swap a cam in there as well. I was really resisting doing any power mods for this car. lol

 

Then don't put a cam in! The cam is what going to start your crack...I mean...power addiction with the car!

 

Hey Duk, Glad you made it home!

Someone here will tell you what the codes mean.

I'd pull the valve covers, check the springs, and crank it. That will tell you if the chain is still connected. We didn't hear any clanking / banging when cranking at the track so you haven't swallowed a valve. I guess the lack of banging is also a good indication the chain didn't break. I also don't remember hearing the motor spinning fast (as if it wasn't developing compression). You could also do a quick compression test.

From looking at that one spark plug, I'm guessing its fuel related as it was completely dry.

 

It's a slippery slope once you start

 

I bought a fuel pressure gauge yesterday, i should've bought a compression gauge as well..doh!

 

how do i test if my fuel injectors are firing? google? lol

 

Ha! I've been a good boy and haven't touched anything to increase horsepower. Want to spend the $$$ on track days, but if I end up replacing the chain, i might as well do the cam...lol

 

Check the pressure at the rail. You should see 58psi. If you don't, look at the fuel relay in the fuse box under the hood, and jump pins 30 and 87 to prime the fuel pump with the key in the "ON" position. This would at least tell you if you have a pump that crapped out. Not entirely sure this is your problem but here is my .02 worth for another angle of troubleshooting.

 

update!

Chain was snapped!

edit:
Been doing a bunch of reading and searching the past few days. I still haven't taken the head off yet, so further inspection of pistons and valves will be done soon.

Starting with what I know now, what's the best replacement for the timing chain?
I've read about the ls2, c5r, the cloyes, and double rollers. I see conflicting information regarding single vs double rollers. What about the cam and crank sprockets? Get OEM replacements or are there upgrade options?

I need to confirm if my car has holes for the dampener, which one is best?

Car is 70% track 30% street car and I intend to keep it that way. With the chain being snapped off I'm going to make some upgrades.

Currently car is stock with just a k&n intake. As of today, I am certain that I will upgrade the cam and headers. I'm still researching on the camshaft, but have learned that no more than .580 lift. I'm leaning towards arh 1 3/4 headers at this point.

My primary goal is reliability and low maintanance. Then, smooth/useable power delivery at the track.

 

Lot of guys running with ls2 chain. I'm running ls2 chain and i'm over 1000hp. But there's nothing bad about the other chains you're looking at if price doesn't matter. Some double rollers had problems with the hitting the cover, so check into that if you go that route. Double is over kill IMO.

 

I had the Cloyes chain NIB still I was going to use till this chain came out
https://www.corvetteforum.com/forums...-no-equal.html

 

Thanks for the link. I'm going to look into that now.

Looks like I found more issues though. A valve snapped on cylinder 5 and the piston is pretty toast. I guess i'm in for my very first engine rebuild! Spirits are high still, although my $$ will certainly be lower.

More things to educate myself on how I should approach this build or even consider a motor swap? Blah!

 

Good luck what ever way you decide to go with your build

 

My '02 has holes for a chain damper but it is an odd width and I couldn't find a damper that was a direct fit.

The codes you have listed make me wonder if something happened to the drivers side of your engine wiring harness (heat or chaffing damage). The MAF, throttle body and CPS wiring is ran through the same loom on the left side.

I have started my engine without a MAF and it should start without a cam position sensor but I don't think it will run if it doesn't sense a throttle body.

I would think that if there is substantial mechanical damage the engine would still try to run.

Check the wiring.

 

Hmm, interesting on the damper hole.

So, which damper did you end up going with?

BTW, found out my timing chain snapped. :/

 

After being held up multiple times awaiting parts and changing plans I decided to skip the damper. I have an A4 trans and am not making a ton of HP. If it was convenient I would have added a damper. I just went with an LS2 chain.

I know there is a damper that will fit somewhere for the LS6 style block but I didn't have any luck sourcing one in time to finish my build. The spacing between the bolts is closer on these. I had seen threads on this forum where the stock holes were filled and re-machined. I wasn't going to go that rout since most of the people who drive the way I do don't have many timing chain issues.


It seems like you think that you broke your timing chain. If that were the case then the valves would have hit the pistons in a more catastrophic failure. You could check your compression to rule this out. If this were the case I would expect to see a different set of codes, a lot of engine noise and smoke coming out of the exhaust. I have seen cam bolts come loose but it is rare.

 

Read thru this thread
https://www.corvetteforum.com/forums...-dampener.html