Hello everyone, I am new to this forum. I am wondering Is there a way throttle body can be reset after cleaning the throttle body to fix the minor vibration in idle on the 2015 CX5 ? Do I need to have a fancy scanner for that?

And is the relearn process a must after the reset? I checked YouTube couldn’t find a proper relearn of the throttle body? Any suggestion is appreciated.

Thank you

 

Disconnect battery for 5 minutes, restart engine with AC, heater, lights, and other electrical load off, allow to idle for 5 minutes then drive normally.

 

Thank you. Follow up question.. Do I need to idle at a specific RPM? Since, my initial relearn is not done correctly, how do I reset it the throttle body into a relearn state?

 

Very rare to need to reset the throttle body after a cleaning in the first place. Not sure how rough you were doing the cleaning? wow! Because and I am assuming you removed the throttle body or at least disconnect the harness it is almost impossible to change the output information in the unit to the ECU? I hope you did not touch the small adjusting screw.
The relearn is generic and even if you did it incorrectly a simple drive will establish the set perimeters. If the idle speed is off, then somehow you did something not normally done in cleaning. You would likely need to completely remove the T/B and look carefully at it.

In a last ditch effort, you can try a hard re-set.
Turn the key to the on/acc position, this means dash lights on but DO NOT START ENGINE. Then slowly push the throttle "SLOWLY" all the way until it is "FLOORED> Make sure that you push it all the way down. There is a spot in the throttle specifically designed to have a greater resistance when trying to go to WOT. (Wide Open Throttle). Then after a couple of second SLOWLY" raise your foot back off throttle and completely take your foot off the pedal. Turn the ignition off DO NOT START the engine yet. Wait a few second then start the engine. Your idle should now be at the perimeter RPM based on the temperatures. You now have done a hard reset of the drive-by-wire. If that is still giving erratic idle speeds, then you may likely have damaged your Throttle body.

 

Thank you for your detail instructions. Throttle body was gently cleaned nothing was touched or played with but after the cleaning, I had reset TB using a OBD scanner. And followed the instruction on the OBD tool to relearn which clearly it didn’t work. Now the car doesn’t run smooth at speed higher than 70km/h. That’s why I wanted to know how can I reset the TB again and relearn it properly so it runs smoothly.

The reason I reset TB is to reset the Idle RPM because the car vibrates when at a red light. There is no check engine or anything. I have also performed the hard reset as you mentioned. Not sure if it worked. Do I need to take it to Mazda?

 

Is it vibrating very harshly, or are you just noticing a slight vibration when the RPMs fluctuate when stopped at a light? That's not uncommon and happens to these cars.

 

Idle RPM has been stable and vibration is pretty much gone after the reset of drive-by-wire. But engine is not smooth at higher speed..

 

You should have also removed and cleaned the MAP/MAS sensors and the IAT sensors when you do a throttle body cleaning. Make sure to use specifically labeled sensor cleaners, These are both very delicate sensors so don't drop them during the cleaning. Let the spray cleaner completely dry before you re-install them.
There are several maintenance procedures that I have done several times to my Mazda that you can review on my thread.
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