SES light costing horsepower?
08-24-2007, 10:24 PM
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SES light costing horsepower? My SES light is on and has been on for a while due to the fact that I have no cats, it's throwing an emission's code, obviously. It's never really bothered me. Some guy told me the other day however that when the SES light is on it puts the computer into somewhat of a "safe" mode and could be costing me horsepower. I thought he was full of it at first but if you think about it, it kinda makes sense. Is this true? My car currently has no tune or o2 sims, which would of course make the light go off.
08-24-2007, 10:44 PM
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I don't know what this "safe mode" is that your friend is talking about. But completely having your rear 02's disconnected without deleting them in the computer, or having sims connected isn't good. The front 02 sensors take a/f readings coming out of your exhaust manifolds/headers while the rear ones take a/f ratios right after the catalytic converters. The computer compares the two and makes sure your cats are healthy, and meeting all emissions. As far as I know having the low circuit codes going off shouldn't have your computer retarding the timing(The loss of hp your buddy was speaking of/or the "safe mode"). But you never know. My advice, buy some 02 sims, and delete the codes.
08-24-2007, 10:54 PM
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rear 02s with sims is the same as deleting them in the tune. the rear 02s dont take AFR readings. your car with SES light will trigger OL and will most of the time cause you to run richer
08-27-2007, 10:29 AM
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Removing rear O2 sensors will do NOTHING to effect power. All they do is monitor the performance of the cats. Nothing else. Only the front O2 sensors have any effect on how rich or lean the engine runs.
Also. You can't delete any sensor. All you can do is tell the PCM to ignore the DTC code. The PCM still detects the lack of the sensor being installed but simply dosen't trigger the SES light.
The only problem you currently have is with the light on you will never know if another sensor fails or something else that would regualrly trigger the SES light.
Re'
Also. You can't delete any sensor. All you can do is tell the PCM to ignore the DTC code. The PCM still detects the lack of the sensor being installed but simply dosen't trigger the SES light.
The only problem you currently have is with the light on you will never know if another sensor fails or something else that would regualrly trigger the SES light.
Re'
08-27-2007, 10:34 AM
#6
Originally Posted by RE AND CHERYL
Removing rear O2 sensors will do NOTHING to effect power. All they do is monitor the performance of the cats. Nothing else. Only the front O2 sensors have any effect on how rich or lean the engine runs.
Also. You can't delete any sensor. All you can do is tell the PCM to ignore the DTC code. The PCM still detects the lack of the sensor being installed but simply dosen't trigger the SES light.
The only problem you currently have is with the light on you will never know if another sensor fails or something else that would regualrly trigger the SES light.
Re'
Also. You can't delete any sensor. All you can do is tell the PCM to ignore the DTC code. The PCM still detects the lack of the sensor being installed but simply dosen't trigger the SES light.
The only problem you currently have is with the light on you will never know if another sensor fails or something else that would regualrly trigger the SES light.
Re'
08-27-2007, 01:21 PM
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Originally Posted by RE AND CHERYL
Removing rear O2 sensors will do NOTHING to effect power. All they do is monitor the performance of the cats. Nothing else. Only the front O2 sensors have any effect on how rich or lean the engine runs.
Also. You can't delete any sensor. All you can do is tell the PCM to ignore the DTC code. The PCM still detects the lack of the sensor being installed but simply dosen't trigger the SES light.
The only problem you currently have is with the light on you will never know if another sensor fails or something else that would regualrly trigger the SES light.
Re'
Also. You can't delete any sensor. All you can do is tell the PCM to ignore the DTC code. The PCM still detects the lack of the sensor being installed but simply dosen't trigger the SES light.
The only problem you currently have is with the light on you will never know if another sensor fails or something else that would regualrly trigger the SES light.
Re'
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08-27-2007, 04:44 PM
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Cool, good to hear some facts on the topic. I didn't think having those o2's out would hurt anything but just wanted to make sure. I'd like to get my car tuned in the future, so I think I'll just hold off on the o2 sims for now and put that $$$ toward the tune. Thanks guys.
