Emissions testing and open loop tuning
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From: Elgin, IL
Car: 1997 Corvette
Engine: LS1
Transmission: 4L60E
Axle/Gears: 2.73 IRS
Emissions testing and open loop tuning
Okay, I failed emissions rather miserably last time I went in (tripled both HCs and COs), and I believe my car was running in limp-home at the time because of a loose connection (has since been fixed).
Anyways, would it be a good idea to burn a chip to run in open loop mode only so I can set everything so the values don't change? Like if I set it with as much timing as possible on as lean a mixture as possible using 93 octane gas just on the virge of detonation, wouldn't it pretty much stay at that threshold in open loop? We don't test for NOx here. Only HCs and COs.
(reading/limit)
HCs were at 2.34/.80
COs were at 44.6/15.0
CO2 was 588.5/NA
Chart was very spikey, but HCs and COs seemed to be related (higher HCs and CO at same time), with the CO chart being much more exaggerated than the HC chart. Also seemed to be somewhat directly related to MPH, but not entirely.
Btw, I also plan on buying a new cat, but I would like to get some ideas for burning a chip to see just how far off I'd be. I would assume its possible to pass even without a cat if tuned properly since NOx are not being tested (meaning I can cut fuel). I just have to ensure all of the fuel is being burned.
Anyways, would it be a good idea to burn a chip to run in open loop mode only so I can set everything so the values don't change? Like if I set it with as much timing as possible on as lean a mixture as possible using 93 octane gas just on the virge of detonation, wouldn't it pretty much stay at that threshold in open loop? We don't test for NOx here. Only HCs and COs.
(reading/limit)
HCs were at 2.34/.80
COs were at 44.6/15.0
CO2 was 588.5/NA
Chart was very spikey, but HCs and COs seemed to be related (higher HCs and CO at same time), with the CO chart being much more exaggerated than the HC chart. Also seemed to be somewhat directly related to MPH, but not entirely.
Btw, I also plan on buying a new cat, but I would like to get some ideas for burning a chip to see just how far off I'd be. I would assume its possible to pass even without a cat if tuned properly since NOx are not being tested (meaning I can cut fuel). I just have to ensure all of the fuel is being burned.
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