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Old Aug 9, 2016 | 08:32 PM
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Default LS6 died

So I am new to this form. Thank you for any help that you guys can give me is appreciated. so I'm working on my girlfriends 2005 Cadillac CTS-V. The car's got a hundred and sixty five thousand miles on it I just did a tune up with new plugs and wire an air filter recently to it. I did notice that the harmonic balancer was wobbling pretty bad on it but didn't do anything about it. The other day it died on her in the middle of driving. The car starts but runs extremely extremely rough.

Went through and tested all the basic stuff have proper battery voltage at the battery. Tested for proper fuel pressure at the front of the rail which was good. Check engine code that is on is a catalytic converter p 0420 I believe. That check engine code came on a couple of weeks prior though. One of my buddy suggested that maybe because of how bad the harmonic balancer is wobbling it could have broke the 24 tooth reluctor wheel. So I went ahead and remove the starter and look at the reluctor wheel through the crankshaft position sensor everything seems to be ok there as far as I can tell. I do have a video of it running for about four to five second but then it shuts off because the motor shaking so badly. I cannot get the video file to upload. Any help from this point would be greatly appreciated
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Old Aug 9, 2016 | 10:55 PM
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Kind of a wildish guess, but if you have a p0420 which i believe is a cat conv inefficient code, then you may have clogged cats.
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Old Aug 10, 2016 | 09:27 PM
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Welcome to LS1tech!

Whenever the damper is wobbling, it's trouble. Worst case, you have crankshaft problems. Best case, the damper itself is shot. Either way, not doing anything about is like driving on a flat tire. You know it won't get better on it's own.

"P0420 Chevrolet Catalyst System Low Efficiency Bank 1"

Yes, it can be badly clogged, blocking the exhaust from exiting the engine can severely affect how it runs. It can lead to other problems from excessive combustion chamber heat build up.
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Old Aug 11, 2016 | 03:55 PM
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My local mechanic recommended I change the crankshaft position sensor which I did. I'm waiting on my new catalytic converter to get shipped in. I did remove the old two catalytic converters and tried starting it with Open Exhaust still won't stay running. Is there any way to upload a video to the site?
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Old Aug 23, 2016 | 06:55 PM
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So I've installed a new harmonic balancer and a new set of catalytic converters still won't stay running
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Old Aug 23, 2016 | 10:45 PM
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While it's running for that short bit or time, is the balancer still wobbling?

Are there any other codes?

When was the fuel filter last changed?
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Old Aug 24, 2016 | 08:57 AM
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Check the crank end play. A new sensor, nor a new balancer, is going to fix that issue. Excessive end play allows the crank wheel to move away from the sensor, killing the signal to the ecm.
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