sickspeedgt

I just installed an O/R H-pipe, and i thought i would need some mil eliminators to keep my check engine line from coming on, but i just bought some last night, and they haven't been put on, but after getting my pipe installed my check engine light isn't even on, anyone else have the same expierience with this, maybe they put some on, or i just didn't need them, or maybe the light will come on later, any ideas.

LIVIN_LEGEND

it takes some time before the light would come on, you should put them on soon because your car will try to protect it self because it will think there is something wrong with the exhaust and run differently

jkm1987

yea mine turned on about two days later so i bought a predator tuner to disable the o2 sensors but they will turn on

Dan04COBRA

It'll come on soon. Some people have gone a week before it came on...

jishead

The computer only tests those downstream O2 sensors under certain conditions like x minutes after the computer reset, x minutes after engine start, x coolant temp, x throttle position and etc. Take a long drive and it will come on for sure I promise! Make the MILs from $0.39 Radio Shack parts if you can solder. Actually, don't buy the caps from Radio Shack. Probably wouldn't stand the heat even if you do find the right uF. Find a local electronics junk store with a bucket of caps and resistors. Search for my previous post on how to make them if you are interested. REmember the check engine light is harmless UNLESS you leave it on so long that it disguises an authentic and more serious problem (unlikely).

sfi

It will come on, even if you disable the o2 through your predator. Once your OBII test is done(20min/XXX amont of mile) it will come on(chk engine light). I had it happen to me a couple of weeks ago. Hook up your mils to your rear O2 and disconnect your battery for 20-30 min. No more chk engine light.

Jiggy_One

The dealer told me that the car goes into a kind of safe mode because it thinks something is wrong with the cats. It pulls your timming back and hurts your power. I felt it first hand with my 04 gt. Your car should run rich when its on pertaining to the emissions stuff. Thats what the dealer told me.

4.6-GetBlown

whenever mine comes on it seems to me that i'm running rich too. i've got MIL's and still get problems every once in a while.

jishead

I could be wrong but I don't think so. Your downstream O2 should not freak out your puter now matter what. The worse that they are suppose to do it turn on your lamp to let everybody know that there is something wrong with your overall emission system. The downstream O2s are NOT used for computation rich/lean by the computer at all. That would be the upstream ones. I have done this on my 1999 Ford Contour and my 2002 Mustang GT and haven't encountered richness. I built my own MILs on both cars. I own a Predator but did not own it when I did my Pro-Chamber / MILs. Once you go with an offroad pipe, regardless of how you shut off your engine light, how will you know if you are running rich? Are you smelling gas? You WILL smell gas with an offroad pipe (or at least I do).

mustang_montana

if you need mils i got a pair of new ones from pony express that i wont be needing (dropping in the s281sc engine soon) ill sell em 20 bucks shipped.