Printable View
Ok please help me out here.
Is having the first O2 sensor (Cali spec) dicconnected going to effect the car performance? Reason I ask is because I picked up some RPW headers, I know no hp gains but I wanted to see the difference in Kamikazee and RPW. Well these have just 1 O2 bung, after the pre-cat so I was wondering if just leaving the first O2 sensor disconnected do anything to the car. Is that safe?
Miguel,
My RPW's had an O2 bung in the front bank of headers as well as the one in the cat portion. I think you're gonna throw SES lights if that first sensor isn't connected. Sounds like you got Fed Spec headers.
So if I get a O2 sensor bung put in will that affect the headers at all?
<div class='quotetop'>QUOTE(Gizmo)</div><div class='quotemain'>So if I get a O2 sensor bung put in will that affect the headers at all?</div>
I am assuming you have a 4 cyl? if so, you bought a header (minus the "S")
You need to run the first o2 sensor or you will run in limp mode and will run well beyond rich. You can go without the rear (post cat) sensor, but will have an SES light, but won't hurt your performance. The first o2 sensor is critical to have.
the front O2 sensor is the second most important sensor on your car.
do NOT disable or remove it.
This is directed at either Zivman or manybrews:
just to satisfy my curiosity as well as some others that may be to bashful to ask...Just why is the first o2 sensor so important and why would the I4 motor run rich without it. Me personally I have looked at and thought about disconnecting the sensor from its plug.
Basically the ecu uses this sensor to determine if the engine is running properly (not too lean). If it is not reading a proper signal from this sensor, the ecu will dump tons of fuel to prevent any damage to the engine as a result of lean conditions.Quote:
Originally Posted by Mante
Yep, the Ecu actualy looks at the output of the first sensor and compares it to the output of the second sensor to determine if the cat is functional. If the readings indicate too wide a voltage span you throw an SES light and go into limp mode.
Not true, kind of. the higher the voltage output, the "richer" the exhaust. The ecu does compare the 1st and 2nd sensor's readings, but the 2nd sensor should be reading well below the output of the 1st. So there should be a wide voltage span (fist sensor should read .8 second sensor should read .15 for example) If you throw a SES code because a lack of or incorrect response from the second sensor, an example of which would be the 1st and 2nd sensors reading exactly the same, you will NOT be in limp mode. I ran this way for nearly 4 months. The ecu does not determine this to be an issue that could possibly damage the engine. If the 1st sensor is not function, the ecu dumps in the fuel as a precautionary measure. The 2nd sensor's function is entirely to show that the cat is working. Again, if your 2nd sensor is the issue, you will NOT be limp mode.Quote:
Originally Posted by Fishboy55
So its ok for the 1st and 2nd sensor the have the same readings? I've had the Kamikazee headers for a while now and the eliminate the precat, so basically the sensors ahve been reading the same.
<div class='quotetop'>QUOTE(Gizmo)</div><div class='quotemain'>So its ok for the 1st and 2nd sensor the have the same readings? I've had the Kamikazee headers for a while now and the eliminate the precat, so basically the sensors ahve been reading the same.</div>
If they are reading the same, you will most likely throw a code. Sometimes this doesn't happen, as it seems in your case. The 2nd sensor should be reading a lower voltage than the 1st. As long as your 1st sensor is reading normally, you are good. The second sensor is there entirely for a check of the cat. If you end up throwing a code, get it read and if it's the 2nd sensor, don't worry about it. You will know if your first sensor is not working. You will have an SES light and your milage will about cut in half.
Just for the record, you bought A HEADER (minus the "S"). https://www.thegalantcenter.org/styl...lt/biggrin.gif
<div class='quotetop'>QUOTE(Zivman)</div><div class='quotemain'><div class='quotetop'>QUOTE(Gizmo)</div><div class='quotemain'>So its ok for the 1st and 2nd sensor the have the same readings? I've had the Kamikazee headers for a while now and the eliminate the precat, so basically the sensors ahve been reading the same.</div>
Just for the record, you bought A HEADER (minus the "S"). https://www.thegalantcenter.org/styl...lt/biggrin.gif</div>
No actually I have 2 HeaderS, Kamikazee and RPW. https://www.thegalantcenter.org/styl...ault/laugh.gif https://www.thegalantcenter.org/styl...ault/laugh.gif
<div class='quotetop'>QUOTE(Gizmo)</div><div class='quotemain'>
No actually I have 2 HeaderS, Kamikazee and RPW. Â*:lol: Â*:lol:</div>
So you had a Kamikazee then bought an RPW header?
<div class='quotetop'>QUOTE(Zivman)</div><div class='quotemain'>
So you had a Kamikazee then bought an RPW header?</div>
Yea I know they don't yield that much hp , but I just wanted to see for myself what the differences were in the both.