Funky s52 problem -- crank, no start.

[Nairb]

1999 OBD1 S52 with about 90k miles.
TRM chip tune.
Vortech v1 supercharged

The other day, I was taking a video of my car. It was running perfectly, as it always does. I went to rev the car a bit. First to about 3k, then to about 5.5k. Once it hit 5.5k, the car sputtered and died out. No weird noises, no craziness. Died as if I had just switched the car off. Checked the video and no smoke or anything out of the exhaust.

Now here is where I (and now my mechanic) are absolutely stumped. We have spark, we have fuel. Changed the camshaft AND crank sensors. Ran a new power line and ground to ECU. Only error message we have received is "1231: Bad Battery Voltage." We have now tried 3 different red-label ECU's and 4 separate batteries. Engine is grounded. Compression is fine for all cylinders. No coolant in the oil or anything.

The car is cranking and sputtering as though it is out of timing, sometimes through the intake and sometimes through the exhaust. We pulled the valve cover and everything is spot on TDC.

Can anyone offer some advice on this problem? The car had run flawlessly up until this point.


And believe me I have searched far and wide for a solution.

[328ijunkie]

Unplug MAF.
Try a different CHip
Try a different crank sensor

[Adrian_Visser]

Checked your Crank hub bolt and harmonic balancer? If the crank bolt backed off you may have sheared the woodruff key between the crank and balancer allowing the balancer to spin, that way the CPS would be reading the wrong timing.

The fact that you have a supercharger belt adding additional drag to the system wouldn't help.

[Nairb]

Thanks for the input, will get back asap.

[Jason89i]

Checked your Crank hub bolt and harmonic balancer? If the crank bolt backed off you may have sheared the woodruff key between the crank and balancer allowing the balancer to spin, that way the CPS would be reading the wrong timing.

The fact that you have a supercharger belt adding additional drag to the system wouldn't help.

this. had this happen to me on a fresh motor at the track. sheered key, no other damage..... except my pride and a trailer ride home.

[ForcedFirebird]

Had this issue with an m50tu swap last week. Turned out the chip went bad, AND the MAF was bad. Like post #2 says, unplug the MAF and try to turn it over. If it catches but doesn't quite run right, then it's the MAF.

Since you tried other ECU's, unless they were all bad, then that should be ruled out.

EDIT: if the crank hub is slipping, the battery won't be charging proper.

[Nairb]

Thanks for all the input.

Yeah we've tried about 5 different ECU's so far, not the computer.

Tried unplugging the MAF, no dice.

The crank hub bolt looks to be in good order, but I am really leaning toward the woodruff key! This seems like the only probable cause because we've damn sure checked almost every other avenue.

Honestly, I have never even heard of a woodruff key before this thread. Do I just remove the balancer and replace the key or do I need a whole new crank hub?

Thanks for all the input.

Hey FF, want to come up and sip some margaritas on Siesta in-between garage sessions? I'll buy.. if you can fix this problem, I am going crazy here! ;)

[ForcedFirebird]

I am from Bradenton, are you really on Siesta Key? Love the "baby powder" sand on the beach there! Graduated Bayshore HS in 94 :)

You realize our shop is only 2hrs away? Hard to get to if the car isn't running though :(

Can't tell you how many times we've been at the daiquiri deck, woohoo! Have pics on the rock jetties at the end of the road just north of the bar, mowahahaha

[Nairb]

Actually no, I live in Bradenton. :(

I would be able to afford a house on the Siesta waterfront if I sold my wife and children into sex slavery, but I honestly don't even know who I would contact to start that process.

I graduated from Bayshore too... in 2005.

2 hours? I thought you were in Miami! But yeah, the car is too low to even get onto a damn car trailer.. I would probably have to remove the valance to even attempt it.

[ForcedFirebird]

Actually no, I live in Bradenton. :(

I would be able to afford a house on the Siesta waterfront if I sold my wife and children into sex slavery, but I honestly don't even know who I would contact to start that process.

I graduated from Bayshore too... in 2005.

2 hours? I thought you were in Miami! But yeah, the car is too low to even get onto a damn car trailer.. I would probably have to remove the valance to even attempt it.

Pics of race car on trailer, its f'ing low. Take the lip off = no problem ;)

[ForcedFirebird]

2005, holy cow. Got some teachers names? Griggy, Perry, Taylor, Grimes (FB coach), gimme something :D

[Jason89i]

T......
The crank hub bolt looks to be in good order, but I am really leaning toward the woodruff key! This seems like the only probable cause because we've damn sure checked almost every other avenue.

Honestly, I have never even heard of a woodruff key before this thread. Do I just remove the balancer and replace the key or do I need a whole new crank hub?......)

pull the #1 spark plug. put the car in neutral, manually turn the crank to TDC. check the timing marks in relation to piston #1. the crank hub has the timing marks on it. if the woodruff key has sheered, then the timing marks will be off. (and the crank position sensor will be telling the dme to spark at the wrong time.)

cheers, jason

[Nairb]

Checked your Crank hub bolt and harmonic balancer? If the crank bolt backed off you may have sheared the woodruff key between the crank and balancer allowing the balancer to spin, that way the CPS would be reading the wrong timing.

The fact that you have a supercharger belt adding additional drag to the system wouldn't help.

this. had this happen to me on a fresh motor at the track. sheered key, no other damage..... except my pride and a trailer ride home.

Winners!

Crank bolt was loose and the key was OBLITERATED. Replaced, and now the car is running wonderfully.

Thanks so much for the input guys, I seriously had not even heard of a Woodruff key prior to this thread, I would've gone berserk trying to fix this problem.



SOLUTION: Crank bolt had loosened, causing the Woodruff key to shear!