i have a 04 mustang with the 3.9 and im pretty sure its goin into limp mode i had exhaust put onto it and it had to have the primary 02 sensors before the cats hooked up...well the guy never put them on...now that i have acouple more mods done such as pulleys intake and others every once in awhile the check engine light will blink and the car runs like pure dog **** and doesnt even have enough power to get out of its own way...but it only lasts for a minute is this limp mode? or wat?....ne help is appreciated..thx

 

I dont know exactally how V6's are set up, but on GT's, the o2 sensors closest to the headders are CURCIAL to your cars performance. They need to be hooked up, as the cars computer uses these sensors to adjust your air/fuel mixture. The rear 02 sensors (closes to the rear of the car) however are not necessary, as they just tell the computer IF the cars are working or not, nothing else. Dont let anybody else tell you other wise. The only sensors that cause "limp" mode are the o2 sensors closest to the headders.


why did he not hook them back up???

 

ive known the guy for years and i made the big mistake of trusting the guy...i should have done it myself but i just didnt have the time...his excuse was that he didnt feel like extending the wires or just buying the extensions therefore making it run rich which it does now...i told him even if he would have charged me more money to re wire them i would have said yea...i could not believe he did that and ill never take nething back to him again...but yea neway he acted like it was no big deal and i tried to convince him that they are primary fuel managment but hes a jackass

 

you don't "have to" hook up the rears, but you'll need either a tuner or MIL eliminators. Any car with a MAF needs the two O2's before the cats, the ones after are merely for emissions. Go back and knock him in the head with a sack of nickles, take your money back and get it done right or do it yourself.

Ryan

 

why would you take your car to a lazy machanic? If a guy working on my car at any time said "yeah I didnt hook XX back because I didnt feel like it" I would imediatly get my entire purchase refunded and the shop made to pay a real mechaninc to make sure the job was done correctally

 

ya thats limping, I had that when my cats were shot

 

yea i have the eliminators hooked up to the back ones from rpm outlet nd he said today he would order the front extensions soo all my bitchin paid off i guess..