Okay- here is the problem. I installed my cold air intake on my tC yesteday. As soon as it was done, I disconnected battery and made sure to let it idle for 5 minutes after I reconnected the battery and started it up. Everything was working fine, and I took it for a test drive. 5 mins into the ride, my check engine light came on. So, I went home and checked everything to make sure nothing was loose, the MAF sensor was on tightly, ect. Then I reset the ECU again, and again let it idle for 5 mins. Everything seemed to be okay again, but after 20 mins of driving, the CEL came on again. I repeated the procedure aforementioned, with the addition of checking the filter for excess oil (there wasn't any). Now I am at a loss. The car seems to run fine, although it idles a tad rough (barely noticeable). I've checked all similar instances posted on these forums, and nothing seems to help. Any suggestions would be very appreciated.

 

buy a obd2 code reader from walmart, about 100 bucks. plug it in and see what is wrong. once you fix the problem just return it, tell them scion is not one of the cars listed.

 

Goto Autozone and they will check it for free! No hasling with returning anything or forking out any of your money.

 

Thanks for the tip. I took it to AutoZone like you suggested, and the results were even more mysterious. Apparently, all four cylinder are reporting random misfires (code P0300). There was also code P0171, "system too lean (bank 1)". the guy there told me this is usually caused by a faulty o2 sensor. Lastly, there was code P0441: "Evaporation emission control purge flow fault." I was told this is usually a minor problem caused by a loose gas cap (although mine was tightened). So, my plan is to replace the stock airbox and take it back to the dealer for repair. My question now is: Is it likely that the intake caused all of this? It doesn't seem to me that any of these things are actually related to the intake, except for maybe the 02 sensor. When all these problems are fixed, should I try to reinstall the intake? What do you think?

 

yeah, that does sound really crazy....keep us posted.

 

maybe when u disconnected the MAF sensor it accidently touched a metal piece of the car which could have shortened it out.....but yes keep us posted.

 

^^nope i shorted mine that way and all that came up was a code for high voltage (high airflow). highly doubt its a busted MAF. just throw the stocker back on and take her in.

 

^^^ yea dats the same code mine threw when it happened i couldnt rev past 3000 lol it was funny driving 20 mph to the dealership

 

i think ur supposed to let it idle for 5 minutes while the car is on, not with the battery disconnected, so it could relearn some stuff...

 

Unscrew the maf sensor and look at the o-ring make sure its not damaged then re-install it and make sure its centered b/c the o-ring isn't that big it has to be sitting perfect. Then go get your code cleared at autozone or advance.

 

I agree. It sounds like a leak at or after the MAF. Make sure the maf is seated properly and check for any leaks. Also, check the seal of any silicone couplers on the intake piping (mainly the one connected to the throttle body)

 

Thanks for the suggestions. I tried everything I could to make sure the MAF was seated properly, but still no luck. I threw the stock airbox back on this morning (still have a CEL), so I'm going to call and get an appointment at the dealer. Hopefully they'll be able to figure it out.

 

btw, while you were installing, it would have probably been a good idea to have to battery unplugged WHILE you were installing instead of AFTER the install.

I'm thinking what they guys have said already regarding shorting is what happened.....

 

i have officially had my bomz intake on and under heavy use for 7 hours and no cel or noises. its perfect.. io think the intake is not your problem.. .

 

I suppose it could be shorting- it's true that I didn't have the battery unplugged. Although, as I was reading other forums about ECU resets, it seems like some people don't ever unplug the battery; instead, they just pull the EFI fuse. If you are resetting the ECU this way, is it necessary to have the fuse pulled throughout the whole install?

 

all i know is i didnt unplug anything.lol. it took me like 20 mins to install everything right. i hope u can fix it. i know it sucks when things are messed up. my window cracked all the way across from a mountain dew can.,...lol

 

pulling the EFI fuse will also work (it doesn't work for me for some reason though), but the only way to TRUELY be 100% sure is to unplug the battery. Also, it's recommended to let the car idle for 15 or so minutes instead of 5.....

either way, take it to a dealership...

 

its kids like you who dont know how to mod cars.. then try, *** up, and go bak to stock and take it into the dealer for repairs..

this is all at cost to toyota corp. which is why they are cracking down on so many people.

if you fuked up your car, take responsibility...

but in all honesty, its prolly cuz you didnt disconnect hte battery, which shorted out the MAF..

and were you listening to your cars stereo while installing the CAI

 

Yeah, I'm sure I'm the only one who's ever made a mistake modding thier car. Besides, I'm sure they'll know I was messing with it, and then I'll have to sell the intake anyways to pay for the repairs. It's not like I know nothing about cars either- I was working on my nieghbors '86 porsche 911 way before I thought about modding my car. Oh, and no I did not have the stero on, nor were the keys in the car.

 

Huh- I just got a call from the dealership. Apparently, despite the throwing all the same codes I listed in my earlier post, they ran tests for everything and everything was okay. They reset the light, and now it's running fine. Wierd.