Celica Forums General Discussion Exterior Intake CEL Troubleshooting Guide

Due to the incredible number of new threads asking about getting a CEL after the installation of an AEM or Injen Intake, I thought I would make a thread about the most common solutions. Mods, if you find it worthy, I would like it stickied.



FIXING A CEL (CHECK ENGINE LIGHT) AFTER AN Intake INSTALL

Complete these steps in the listed order, do not skip around.


Step 1:
Check ALL of the vacuum lines and make sure that each one is attached correctly and is in the right place.


Step 2:
Check to make sure that the MAFS (Mass Air Flow Sensor) is inserted into the Intake pipe correctly.

The MAFS is shown in this picture, it's the large black square on the Intake pipe.



It's in this photo as well.




Step 3:
If you are positive that all of the vacuum lines and the MAFS are in their correct places, the next step is to reset the car's ECU (Engine Control Unit, the car's brain).

Follow these steps:
1. Disconnect the negative battery terminal (the black one).
2. Let the car sit for AT LEAST 15 minutes, it's recommended that you wait a half hour.
3. Reconnect the battery terminal and start the car to make sure that it's connected properly.


Step 4:
Clean the MAFS. Follow these instructions EXACTLY.

https://celicahobby.com/ubbthreads/thread.f_1862388016_0_collapsed_2__1.html

You are trying to clean the 2 air flow sensor wires which live inside of the MAFS. They are small and hard to see, but they're there and expensive to replace. You also need to clean the contacts between the wiring harness and the MAFS housing.



Step 5:
If you complete all of the above steps and the CEL remains, take your car to either your Toyota dealer or an auto parts store and ask them to check what CEL code the ECU is throwing. You'll recieve and number and about 5 words which will give a small description of the problem. Be sure to write the code down so you can post it, and we will try to help you troubleshoot what it is and how you can fix it. We're here to help.

^^^it's about time someone put up a guide for that problem..

Good job..the guide should clear up any problem from here on out..

good...very informative

good job man.. people are always askin and i have to repeat myself so many times by the way in step 3 you should metion that when you turn the car on you cant touch the pedal for like 15 minutes at all or it will like kill the ECUs automatic adjustment..

Can't edit it anymore.

also note that some CELs are caused directly from the Intake itself, so dont think your car is totally f-ed up if you try everything and are unable to fix the CEL.

^^true dat..

Ninja bump.