07 mustang gt mac lt headers problem help!!!!
05-27-2009, 04:10 PM
#1
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07 mustang gt mac lt headers problem help!!!!
I just installed mac long tube headers on my 2007 mustang gt. It took me 8 hours to do this for far i have jlt intake flash tune borla cat backs. Everything went smooth but i have not conected the passenger o2 censor i have the o2 extetion on order. The problem is that my car wast to much gas i dont know if because of o2 censor is not connected or its someting i did wrong. I have a off road x pipe and the headers are 1 3/4 if some one could give me some addvice i am new to this thanks.
05-27-2009, 04:24 PM
#2
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If it is the 02 sensor closest to the engine, then yes it will burn too much gas because it has no way of checking the a/f ratio and it will default to a rich condition for engine safety. if it is the 02 sensor closest to the rear of the car, you are worrying for no reason.
05-27-2009, 04:50 PM
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ok sounds good what a relief thanks i ask around and they told me i needed to get custome dyno tune and that $400. Or another thing is that the headers are to big for stock motor and normaly ill get 18mpg city/ 27 highway now i get 15city/23 highway which is bad.
05-27-2009, 06:40 PM
#6
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I don't see how the headers can be too big for the motor, they are designed for the GTs 4.6... are you sure the gas mileage drop isn't due to your right foot and the new found power and sound?
05-27-2009, 06:46 PM
#7
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no its not my right foot i try driving slow than usual i shift around 2,500 rpms insteas of 3,000 but i have the 1 3/4 mac lt and they told i should have gone with 1 5/8 but like how linde said i just need to connect the passenger header o2 censor i just the extentions which i have on order so hopedully thats the issue
05-27-2009, 07:05 PM
#9
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When I put JBA shorty headers on my car, my fuel economy went up 3 mpg highway. Make sure you retune your car with your tuner when you get the 02 extension so your car can relearn to use that sensor and not run so rich.
05-27-2009, 07:15 PM
#10
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yeah i love them too its sounds great!! with my frpp stingers every one tells me what set up i have so i cant wait untill i get my shipment with my o2 censor extentions its my daily car so its really eats gas like crazy and i have limit the use of my car because of that and i love driving my baby around