Running an o/r mid pipe w/ no MILs
04-12-2008, 12:44 AM
#1
3rd Gear Member
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Join Date: Sep 2006
Location: El Paso, TX
Posts: 700
Running an o/r mid pipe w/ no MILs
So a few days ago another member posted about his car running like crap after a full exhaust install. He was running an o/r mid pipe and it was suggested that the MILs installed were probably not functioning. Sooooooooooooooo my question is, will my car run like crap if I don't install MILs?I don't get my MILs 'till about next friday. I was planning to run MIL-less 'till then.
04-12-2008, 12:47 AM
#2
5th Gear Member
Join Date: Jul 2007
Posts: 3,731
RE: Running an o/r mid pipe w/ no MILs
It will run like crap. You'r car's computer is going to want the values from the rear O2 sensors, and if you don't have cat's, I don't think it has either the rears or the front's. But regardless, it won't be getting the signal, and it will go into limp mode or whatever
04-12-2008, 12:57 AM
#5
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RE: Running an o/r mid pipe w/ no MILs
i tried to save enough for a tuner, but they are just too expensive for me right now. I came across a good deal on MILs and took the chance. Darn it,I guess I'll have to wait 'till I get the MILs. Thanks for the input 2000AZ5.0GT.
04-12-2008, 03:39 AM
#6
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RE: Running an o/r mid pipe w/ no MILs
I am not running MILs with my off road mid pipe and the car runs just fine. It is also getting better gas mileage so I am just going to hang onto the MILs in case I need them in the future.
04-12-2008, 07:41 AM
#7
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Location: Ohio
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RE: Running an o/r mid pipe w/ no MILs
Holy crap how many times is this going to come up and how many times are people that have no clue how a car works going to keep giving bad advice. YOUR CAR WILL NOT RUN LIKE CRAP WITHOUT MILS. THE REAR O2s HAVE NOTHING AT ALL TO DO WITH THE METERING AND FUNCTION OF THE ENGINE. THE COMPUTER ONLY COMPARES THE READING FROM THE FRONT O2s AND THE REAR O2s. IF THEY ARE OUT OF SPECS THEN THE COMPUTER TURNS ON THE LIGHT. THE CHECK ENGINE LIGHT THAT COMES ON ONLY MEANS THAT YOUR CATS ARE NOT FUNCTIONING AND YOU WILL NOT PASS EMISSIONS. THATS IT!
04-12-2008, 10:18 AM
#8
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RE: Running an o/r mid pipe w/ no MILs
Yep the rear O2's do nothing more then monitor catalylitic efficiency, not sure where the old wives tale of your car running like crap and getting terrible gas mileage came from.
04-12-2008, 12:04 PM
#9
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RE: Running an o/r mid pipe w/ no MILs
ORIGINAL: oxfordgt
Holy crap how many times is this going to come up and how many times are people that have no clue how a car works going to keep giving bad advice. YOUR CAR WILL NOT RUN LIKE CRAP WITHOUT MILS. THE REAR O2s HAVE NOTHING AT ALL TO DO WITH THE METERING AND FUNCTION OF THE ENGINE. THE COMPUTER ONLY COMPARES THE READING FROM THE FRONT O2s AND THE REAR O2s. IF THEY ARE OUT OF SPECS THEN THE COMPUTER TURNS ON THE LIGHT. THE CHECK ENGINE LIGHT THAT COMES ON ONLY MEANS THAT YOUR CATS ARE NOT FUNCTIONING AND YOU WILL NOT PASS EMISSIONS. THATS IT!
Holy crap how many times is this going to come up and how many times are people that have no clue how a car works going to keep giving bad advice. YOUR CAR WILL NOT RUN LIKE CRAP WITHOUT MILS. THE REAR O2s HAVE NOTHING AT ALL TO DO WITH THE METERING AND FUNCTION OF THE ENGINE. THE COMPUTER ONLY COMPARES THE READING FROM THE FRONT O2s AND THE REAR O2s. IF THEY ARE OUT OF SPECS THEN THE COMPUTER TURNS ON THE LIGHT. THE CHECK ENGINE LIGHT THAT COMES ON ONLY MEANS THAT YOUR CATS ARE NOT FUNCTIONING AND YOU WILL NOT PASS EMISSIONS. THATS IT!
04-12-2008, 12:08 PM
#10
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RE: Running an o/r mid pipe w/ no MILs
THE COMPUTER ONLY COMPARES THE READING FROM THE FRONT O2s AND THE REAR O2s. IF THEY ARE OUT OF SPECS THEN THE COMPUTER TURNS ON THE LIGHT. THE CHECK ENGINE LIGHT THAT COMES ON ONLY MEANS THAT YOUR CATS ARE NOT FUNCTIONING AND YOU WILL NOT PASS EMISSIONS. THATS IT!
Yea. It's crazy some of the misconceptions that people get.
I don't mind so much someone coming in and asking about it, but when people who obviously have no idea start giving bad advice, I can understand getting frustrated.