Got O/R Prochamber Installed..


Active Member
Mar 15, 2006
Well I finally got it installed. We did the radioshack MILs. Well on the way home my CEL came on. Guess they didn't work. I have no problem getting the plug and play ones, but for the time being my question is....Is the CEL just a CEL or will it start to run bad? BTW, it sounds AMAZING! :nice:
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The CEL won't give you any performance issues. I ran mine for several months like that.

Actually from what I have heard it does give you performance issues. Your car is told "hey don't run as hard as you can, something is wrong" so you may think your car is the same, but really you are running at 90% or whatever it de-tunes itself to. My friend gave me the insight one Saturday morning about a year ago and said "you know you are not getting all your horses because your CEL is on..." Needless to say we were straight off to Mustangs Unlimited and YES there was a big performance difference when I hooked them up. The other downside of "living" with the CEL on is you are not aware of other problems. Once I got the MILS my CEL went off for a few months but then came back on and it was because my IMRC's were either dirty or needed a new module for them to operate correctly. Moral of the story you will lose horsepower and you may be overlooking other critical codes that may be thrown that are relevant to your performance.

Personally, I have finally fixed ALL CEL codes(they come more frequently when you mod your car a lot...), cleaned IMRC's, and replaced the IMRC module and my car is at least a second faster in the 1/4 than it was before - that I can promise!
Oh yeah, before you say your stock MILS aren't working get a code pulled (Free at Autozone) and make sure it's not something else - I thought after a few months that mine must have gone bad when really it was a whole BIGGER problem!
I agree with tmoney about getting the CEL checked to make sure it is in fact the O2's. Also with what he said, I'm not sure if the car will go into a "limp mode" because of the CEL. It's been a while since SN had a discussion on limp mode :)
I planned on getting the codes pulled soon, but it came on after 5 minutes of driving after the thing was installed so I am pretty sure it's a code from one of both of the 02's. But it seems to be running fine right now..
ive got a friend of mine that has been a line tech for ford for 25 some odd years, and i got wo words "limp mode" jim says any time your cel comes on you comp. depending the code is how much your comp. will detune the engine. and if the if the rear o2s arent important and did not effect the cars performance ford wouldnt had put them there, oh and im willing to argue this point. and like i said if they werent important and didnt have any effect on how the car ran THEY WOULDNT BE THERE... I know ive been in the same situation, and didnt beleive it so i had it dynoed with cel on for the o2s and had it dynoed with the cel off and there was 18hp difference so GET IT FIXED.
"Limp Mode" only applies to automatic transmission failure. If the PCM determines that there is something wrong with the automatic transmission, it will go into limp mode to help save the transmission from any further damage.

Now in regards to engine performance, there are things CMPFM(Camshaft Position Failure Mode) and FMEM Failure Mode Effects Management when there are malfunctions with the CMP sensor and PCM respectively.

The rear O2 sensors are only used to measure catalyst efficiency and have no direct affect on the performance of the motor.
then tell me this, laser red, if you have a clogged cat to much backpressure will chew the exhaust lobes off the cam, so ford designs the comp. to detune the engine to cut down exhaust pressure by cutting fuel pressure to the engine, like deisels do when the exhaust temps get to high...