LeMans05C6

Alright to prep this story I will let you know I got some long tube headers put on Thursday. I had the car tuned as well.

That night and next morning I had an issue with starting the car. Have the clutch in and press the start button and it would just make the electrical sound over and over but not even try to move the engine. I would turn it off and let it sit for a second...try it again and turned right over.

Well it happened once more Friday mid-day so i took it back to the guy who tuned it and we couldn't replicate it so its hard to diagnose a problem when it wont do it.

I was at Eagles Canyon this weekend. Fun track lots of straight and pretty hard on brakes. My rears i think barely made it through but probably have very little left on them, but thats why I have the rear pads and rotors on order.

Anyway.... the bad news.

The last session (typical I am sure for bad track weekends) probably my 2nd lap coming down the first long straightaway but not that far down it the car just loses pressure is the best way to describe it.

No leaks, no big knock when it died, just sounded/felt like the throttle was no longer making any power. And lost most power systems. Brakes weren't really there nor was steering really.

I checked the belts were still on, after it got towed off the track they said I had fuel pressure when people checked the rails. Had 3/8 tank of gas so plenty there. Battery isn't dead as its not that sound.

It will no longer start, but now its a different sound that before. Instead of what sounded more of a quick electrical thing trying get going that never would, the engine tries to turn but won't ever fire more than once or twice. Its odd

Some said it may have been timing as I think they were guessing, others were as clueless as I.

Talked to my turned about it on the drive home with the tow truck, and when he installed the Headers there was one 02 sensor that may not have been 100% but seemed to be fine during the tune and install. The other question he thought may have been me running the car that hard the cats (which were used and sounded okay at the time) may have seen the end of thier days which would be sending a wrong message back to the ECU.

I am sorry this isn't the best explanation, but if anyone has come across this or has any idea please shoot them my way. Just trying to get all the info i can from corvette minds.

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10/20/2010 Update

Well the mechanic shop had been waiting for me to make up my mind on what I wanted to do. Finally decided with some help and shopping around.

The problem WAS NOT the timing chain actually. Not sure if its better or worse, but the cam bolts got sheared off.

The ASP pulley was on there pretty tight (and i have read things saying ASP pulley's have lead to timing chain breaks). I ran it through my fingers and didn't feel any stiff links as at all. So a small ray of hope for the ASP pulley group. It may have had a little wobble under idle but with any throttle always looked very smooth and steady in place.

I got phone pics but can't upload at work.

The cam bolts had shear off at the cam, oh darn.... now i HAVE TO get a new cam. My heads with the imperfect valves are going to TEA to get thier stage 2 CNC work done on that and have new valves installed. As the pistons got kissed on most of them but not major damage, i had thought about replacing the pistons but have decided to go with a 402ci stroker kit (4.000borex4.000 stroke) instead and have the bottom shortblock rebuilt with forged internals. Never gonna do FI so won't ever see more than 550hp on a perfect day with even more done to my car, but the parts going in should easily withstand <600hp.

I should get picture updates of the build process and hopefully get some as it all goes back together, but for now its shipping my block off to get rebuilt and the same with my heads.

ErnieN85

I'd check the cam chain first! if it jumped and hasn't broken anthying you might be lucky.

rag1998

Sorry to hear about your troubles.

Really hope you get it all sorted out. On the bright side I bet you had fun @ eagles canyon!

LeMans05C6

Very different track than Cresson. Longer straights, definitly got more comfortable with Heel-toe as shifting is necessary with all those long straights. It was bumpier than i would have guessing. I mean I heard it was from people at Cresson who i talked to but its only 3 years old and I hear they have been fighting it for quite a while to get it right. Either way its good to experience a new track and see what your made of when you start from scratch.

As things go looks like ill be taking to get worked on tomorrow. Any other ideas, let me know please... Ill keep you guys informed as it is diagnosed.

63Corvette

I would take it to a mechanic with diagnostic (computer) equipment. I would bet they will have your answer quickly. Are you near LGM? Sorry to hear about your problems. And yes, Eagles Canyon is hard on brakes.

TedDBere

What codes is it throwing?

Madkarter

Which car where you. I have the white Doug Rippie car. I always take a tech 2 scanner with me to the track. John Page from 21st century was pitted behind me. So don't be stranger if you need help at the track.

LeMans05C6

I was in the blue C6 in the HPDE Group. #27.

I saw both of your cars out there. The white one with the orange accent I saw in TTU was fast. So the the 21st car with the blue and red stripes.

This was the last session of the whole weekend so most everyone was packing up and gone. Thanks for the offer.

tcmc5

Cats shot/clogged? Try running it with open headers.

LeMans05C6

My tuner had that idea as they headers were used and i ran with cats this weekend. Lots of high speed so the cats may be toast now but i can't check yet, i could poke them with something see how they sound... ill try that later tonight. Gonna get the car to him and have him check the O2 sensors and give him the straight pipes as well to try out and hopefully when he gets a computer and code reader on it he can get an answer much quicker.

VetteDrmr

I'd aim towards the cats as well.

Here's a theory: If you have an exhaust leak, the O2 sensor will see the extra O2 in the exhaust gasses (the leak will actually suck outside air into the system), and the PCM will enrichen the mixture. This continues to get worse as the O2 continues to be present.

All of this excess fuel lights off in the cats, and gets so hot the matrix melts. I've experienced this one time, and when the cat matrix melts and turns into a lump I lost power and just pulled off the side of the road.

One thing's for sure; you're going to have to get with your tuner to figure out what's wrong.

Good luck, and have a good one,
Mike

LeMans05C6

My tuner had the same idea. If a faulty O2 sensor combine with the possiblity of a cat going bad then its going to think things are wrong when its not. Nice to see someone come up with that same idea as well.

I need to tap my cats tonight and see how they feel. Maybe they melted.

If thats the case. OH darn i have to run straight pipes for a bit. Would be really nice if thats all it was. I am hoping it is since I really didn't hear anything major and it was under wide open throttle but not high RPMs since i wasn't even that far down the straight in the video when it died.

Timz06

Your problem is not a cat. I would guess you have an electrical problem, probably a shorted wire or missing ground from the header install. Check the easy things first like all of the fuses. Check to see if you have spark. If you have fuel and spark and the car wont run, you have a more serious internal issue. Good luck, whenever you start modding a car, be prepared to spend a lot more time working on it.

Tim

*C7*

I don't see the CATS or the O2 sensors keeping the engine from starting.


Good luck with this.

VetteDrmr

O2 sensors won't, but I know from first hand experience that a plugged cat will. The Vette is helped somewhat by running a true dual system, but only helped.

Also, checking for a dead cat (no pun intended, I'm a cat lover) is fairly easy to do.

Always take care of the "low hanging fruit" first before heading off into the electrical depths.

Have a good one,
Mike

CorvetteZ51Racer

This to me is the main clue that it is not ALL the cats. Could you have a cat problem, definitely. But the morning after you got it back, to have trouble just getting the motor to roll over, is not a cat problem. There is an electrical issue somewhere, with the possible addition of something relating to the exhaust.

Check the low-hanging fruit, but don't throw out some of your clues just because they don't fit a theory.

VetteDrmr

At this point nothing is out of bounds.

LeMans05C6

Well either way I gotta get it towed to my tuner and then he gets to dig into the problem. Just crossing my fingers for minor vs major.

waddisme

Did it throw any codes? Seems like any issue with O2 sensor would throw codes to alert you. Hell, I don't even have issues and my O2s and they throw codes (P0133).

Zosickness

This^ like Ernie said.

I've had the same problem with my car. It was my timing chain that had snapped on me. Just like you described. Don't keep trying to start it either. On one attempt to restart mine after a couple tries a cylinder fired and it blew a hole in my intake manifold. Unfortunately that wasn't all that happened. I bent some pushrods and it wiped out a couple lobes on my cam when the chain snapped.

Hopefully, yours is something simple.