Toyota Yaris DIY

Tools needed: metric or SAE wrench set, hex key set, utility knife, phillips and flathead screwdrivers, time and patience!

Time Allowance: Took me 2 hours from start to finish. (Those more mechanically inclined probably will take an hour).

This DIY is for the newbies or anyone who has never attempted to do this.

A modified or aftermarket intake has many advantages over the OEM airbox: among these are increased airflow to the engine boosting horsepower (a wee tiny bit), cooler engine running temperature (some here have reported a 10 degree drop), and a more agressive engine sound from underhood!!!!

NOTE: You may choose to do the steps in an order different than I did. Don’t bitch me out if you didn’t do yours like mine.

NOTE: Your results may be different than mine were. I am not responsible for your installation.

NOTE: If you receive a check engine light after installation (CEL) you did something wrong. DO NOT continue to run your engine if you receive this warning!!!!

Part 1: Deconstruction of OEM Airbox

1. Disconnect your negative battery cable as a precaution and to reset the Engine Control Unit (ECU).

2. Undo the OEM top airbox metal clamps to loosen the airbox. Remove airbox filter. Observe the dirt! Yucky.

3. Using phillips head screwdriver, unscrew the two small screws holding the Mass Air Flow connector (MAF) from the airbox. Also using flathead screwdriver pry the MAF wiring plastic anchors from the airbox.

4. Once the MAF connector and wiring is free from the airbox pull the MAF sensor carefully from inside the airbox. You may have to wiggle it a bit to get it out. Dont knock this little thing around it costs a lot of money and can cause you a check engine light upon reinsertion. Be nice to it.

5. Disconnect the PVC hose from the airbox inlet pipe. To do this pinch the hose clamp and move it back away from the clamping point then pull the hose off the airbox. Tug it good and it will free.

6. With all hoses and wiring free from the airbox, go to the clamp that connect the airbox hose to the throttle body (TB = silver metal part). Using a phillips head screwdriver untighten the screw holding the clamp. When loose, move the clamp around and away from the clamping location.

7. Using a flathead screwdriver gently pry the airbox hose off of the throttle body pipe. Use some force here as that thing is TIGHT on the pipe. After removing airbox clean TB pipe area.

8. Remove the upper airbox component from the engine compartment.

9. The lower airbox component is secured by two bolts. Using a wrench remove these bolts then remove lower airbox from engine compartment.

This completes part 1

Part 2: Installation of Intake System

10. Insert assembled intake into engine compartment to test fit. Do not secure clamps at this time. Insert intake silicon connector to throttle body to test connection. This fitment must be tight with no vacuum loss (air escaping from connection). Adjust if neccessary.

11. Once fitment is correct tighten two supplied metal clamps to intake throttle body silicone connector.

12. Tighten two supplied metal clamps to intake filter element end.

13. Remove 4 nuts from engine cover and remove it. This is done to access the PVC hose coming off engine block.

14. Remove PVC hose from engine block by squeezing the clamp on hose and
moving back from clamp point. Tug the hose and it will come off for removal.

15. Measure new PVC replacement hose supplied with intake for fitment. The new hose will connect using the OEM factory clamps at both ends of engine block and intake pipe.

16. Cut the black tape that connects PVC hose to other hose in engine compartment. This will free hose to be removed from engine compartment.

17. Cut new supplied PVC hose with utility knife after test fitment. Ensure you have not cut the supplied pipe too short to fit on intake pipe from engine block.

18. Connect PVC pipe at both ends using factory clamps. Replace engine cover and tighten nuts.

19. Recheck all clamps, hose connections for tightness.

20. Start engine, let idle for 5 or 10 minutes for ECU to adjust to intake. Check for any Check Engine Lights (CEL). If you get this response turn engine off and recheck all hose mounts and clamp mounts.

NOTE: The intake I received came with a chrome mounting bracket shown in the pics. I have not used it yet but am planning to as an intake can bounce around a bit depending on vehicle motion and engine RPMs.

That’s it. Enjoy the more aggressive sound coming from your engine bay.