PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

tuning issue?

Old May 4, 2011 | 10:06 PM
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Hi this will be my first serious thread as i just signed up tonight but ill get right to it. Anyway i have an 01 sierra 4x4 with the factory 4.8 and up until this week i have had a home built rear mount turbo setup with an HP tune done on the dyno (not by me).
all was well for about 9 months of tire shredding when i decided to rebuild the turbo kit under the hood up on the passenger side of the engine bay, i deleted the cats and made both my upstream o2's 4 inches away from the manifolds (like stock) and finally got it all together pretty like and gave it a crank to my surprise it is running the worst I've ever seen it. first off i can barely keep it running at any rpm range no power at all, its like its super rich because i can hear the turbo spooling at very low speed low load conditions, so i experiment with the o2's and i can unplug both with no ill effects at all.

this is not what i expected to happen at all it ran great before i changed some pipes around and took off rear o2's now i have a 5800 lb boat anchor pretty much. any thoughts?
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Old May 5, 2011 | 06:40 PM
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Data logging and checks for vac leaks, exh leaks, all sensors and elec connections is where I'd start.
Map sensor is working?
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Old May 5, 2011 | 06:46 PM
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i assume its working, i have no way to check, its only 9 months old anyway. Isn't there a fuse that the o2's run off of?if so what is it labeled as? I'm wondering about this because it runs the same with or without o2's like they have no power to them.
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Old May 6, 2011 | 07:37 AM
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It's kind of difficult if you can't data log, do any checks...Someone around that can scan the system?? EFILIVE, etc..
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Old May 6, 2011 | 07:59 AM
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The o2's should run off of the engine fuse. I'll have to check how it's exactly labeled in mine.
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Old May 6, 2011 | 05:37 PM
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i appreciate that, i know the trimming runs off a fuse but i have no idea what or where it is...
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