Okay, couple of questions here, so bear with me please.

I installed an AEM CAI on my car maybe a year ago, and added an exhaust to it a few months later. Well, a few months back, my car started riding sluggish-- it wouldn't be responsive when I stepped on the accelerator. Then the check engine light popped up. Cleaning out the MAF madeit infinitely more drivable, but I felt I needed to buy an A/F gauge to regulate the mixture going into the engine-- and it worked to remedy the lean A/F ratio for a time. HOWEVER... after a few weeks, it looks like the car is reverting back to its sluggish form and I'm at wits end trying to fix it.

What I'm wondering is... has anyone here actually had success with or know someone who has had success with an A/F ratio monitor in the past? Some of these monitors, mine included, piggyback onto the ECU and are effective for a short time, but will eventually be overridden by the ECU and be rendered useless. Some Celica users noted similar problems, but found success with a particular kind of A/F monitor so I know it can sometimes be due to the particular model. If anyone has had any kind of succes (more than 2 or 3 weeks) or knows of something beyond sales claims, I'd certainly appreciate it!

a/f guages don't modify ANYTHING. They don't do anything but convert the signal from your o2 sensor to a gauge for you to see what the sensor sees. Nothing gets changed or modified.

Did the intake you put on have an oiled filter? Do you have everything snug and tight? Do you have one of those "bypass" filters on it? What other mods have you made? When you say you put an exhaust on it....what type of exhaust?? header? catless pipe? catback? muffler??

The 3 has the same MAF as the 1.6L. They are notorius for CELs and hesitation when intakes are added (except for the Simota, lol).
One thing that seems to help is disconnecting the battery BEFORE you remove the stock airbox. Maybe you should go back to stock and then reinstall the intake.

w3rd

Sorry, I sure butchered that-- not a GAUGE, something akin to an EMS-- in order to try and correct the A/F ratio. So far, the only one I've heard anything resembling positive feedback on is the Unichip EMS, or possibly Emanage.

The exhaust is a cat-back, and yes, everythings oiled up, tight, and in place. I may end up just having to remove the CAI, but I was trying to avoid that if there was a way around it. Thanks though

you need to switch intakes. Get the Thunder Racig intake from Kargoboy. no'ones reported any problems with it on the new cars.