GR Yaris Inconsistent Boost

I am suffering low boost, what was the outcome off this in the end?🚗💨
The ECU strategy limits boost in certain situations to protect the engine, because OEM, warranty etc.

Whether you find that to be reasonable/tolerable is up to you.
 
The OEM ECU is like grandma sitting in the back seat saying "well f&*k you, you can't do that". o_O
It’s had Collins remap, been running bang on!
Even put the original airbox back on, and changed the boost solenoid, will do the 20 mins re boot, then different fuel 🤷‍♂️🚗💨
 
It’s had Collins remap, been running bang on!
Even put the original airbox back on, and changed the boost solenoid, will do the 20 mins re boot, then different fuel 🤷‍♂️🚗💨
What fuel are you running and when is it happening?
 
It’s had Collins remap, been running bang on!
Even put the original airbox back on, and changed the boost solenoid, will do the 20 mins re boot, then different fuel 🤷‍♂️🚗💨
Recent remap? My first revision of the Litchfield EcuTek map kept randomly falling off boost between gear shifts and they said they and possibly others have seen the same thing under certain conditions so have since revised it. In my instance it was all captured on the app. Reflashed with revised map and all good so I’d advise getting back in contact with Collins perhaps.
 
It’s had Collins remap, been running bang on!
Even put the original airbox back on, and changed the boost solenoid, will do the 20 mins re boot, then different fuel 🤷‍♂️🚗💨
that’s what solved it for me. Original box and MAF sensor placement etc + the 20 minute battery-off-reset thing.

Returned the Forge box and filter.
 
I am suffering low boost, what was the outcome off this in the end?🚗💨
In the end just like what @Sturesmyg said, put back CAI to stock standard or go ecu management system.


I did everything I could, (delayed putting my stock box, because I liked how the MST sounded, but also paid a good chunck of change for it!!) but in the end that’s what seems to solve the problem.


It might be a bit unfair as I have friends who have open pod filters and eventuri etc, but my guess is the stock ecu on this car is shit and doesn’t allow a lot of tolerance (for SOME, not all cars, like my own). Coming from European cars, I think their ecu has a much high threshold when you introduce a CAI/Exhaust as you’re changing how much air is now going into the car. I think this ecu in particular as the guys at Motive have said, this is one sensitive ecu. As soon as more air is introduced, the car probably freaks out and pulls back boost as it’s recognising more air is coming in, but is unable to change the fuel ratio to match.


Stand-alone ecu would be awesome, but very expensive, although I’m sure you could leave on your intake that you paid for a fraction in price compared to the ecu lol
 
Does the MST have a different inside diameter tube where the MAF is located compared to the OEM air filter housing?.
 
In the end just like what @Sturesmyg said, put back CAI to stock standard or go ecu management system.


I did everything I could, (delayed putting my stock box, because I liked how the MST sounded, but also paid a good chunck of change for it!!) but in the end that’s what seems to solve the problem.


It might be a bit unfair as I have friends who have open pod filters and eventuri etc, but my guess is the stock ecu on this car is shit and doesn’t allow a lot of tolerance (for SOME, not all cars, like my own). Coming from European cars, I think their ecu has a much high threshold when you introduce a CAI/Exhaust as you’re changing how much air is now going into the car. I think this ecu in particular as the guys at Motive have said, this is one sensitive ecu. As soon as more air is introduced, the car probably freaks out and pulls back boost as it’s recognising more air is coming in, but is unable to change the fuel ratio to match.


Stand-alone ecu would be awesome, but very expensive, although I’m sure you could leave on your intake that you paid for a fraction in price compared to the ecu lol
I do love my MST , and it’s cost a lot, I have put std std airbox on and it’s the same, have disconnected the battery for an hour, but not tried it yet, as my back has failed me!
I can see me going ecutec or syvecs, I intend to keep the car so will have no issues in the future 🙏🚗💨
 
Has anyone who’s suffered from this issue changed the MAF sensor yet? I wonder if the P/N has been superseded or if there is a variance in part numbers between manufacture years etc? I maybe barking up the wrong tree but surely it’s just a case of software & sensor outputs?
 
Has anyone who’s suffered from this issue changed the MAF sensor yet? I wonder if the P/N has been superseded or if there is a variance in part numbers between manufacture years etc? I maybe barking up the wrong tree but surely it’s just a case of software & senso
 
Same thought, I'd be interested to know. My car is a 2021 year
 
From what I recall the MAF sensor is not specific to GR Yaris, and is shared across many models. I believe even the highlander, and the likes of Lexus GS use it

If you're going to go down the rabbit hole of just going brrrrrt with the parts canon, may I suggest you simply purchase a ECUTEK tune and be done with the issue entirely
 
From what I recall the MAF sensor is not specific to GR Yaris, and is shared across many models. I believe even the highlander, and the likes of Lexus GS use it

If you're going to go down the rabbit hole of just going brrrrrt with the parts canon, may I suggest you simply purchase a ECUTEK tune and be done with the issue entirely
Ecutek was my solution, remap last week.
Anyone know if ecutek software is standard or differs to the tuner?
 
From what I recall the MAF sensor is not specific to GR Yaris, and is shared across many models. I believe even the highlander, and the likes of Lexus GS use it

If you're going to go down the rabbit hole of just going brrrrrt with the parts canon, may I suggest you simply purchase a ECUTEK tune and be done with the issue entirely
Assuming an ECUTEK tune re-calibrates the MAF resistance values tells me it’s hard written into the ECU’s tables that can’t be simply reset/recalibrated with a battery disconnection for 20 minutes procedure.
I’d have thought the MAF has a calibrated setting that doesn’t adjust from the factory’s initial hard coded parameters. The setting may adapt/adjust to expected MAF degradation over a set period of time but not allow for a sudden increase of airflow eg new intake/increased diameter pipework etc.


It maybe that a recalibration of the MAF can be performed on Techstream if it’s anything like VCDS/Vagcom but alas, I don’t have Techstream but plan on ‘obtaining’ it somehow.

People changing their intakes are sporadically having these issues. My first thought would be the MAF.

This is all theoretical on my part & I may be completely wrong but, hey, it’s a discussion 😊
 
back in the days we were hunting possible MAF issues by measuring the sensor voltages it provided vs reference values when idling. not so sure how these modern cars work, that was RS2 style MAF in Porsche 968 back then. usually MAF detoriates by age / abuse, as so low mileage car would find it difficult that MAF could be gone but everything is always possible.
 
I don’t think modern MAF sensors are too dissimilar, a heated wire (platinum?) & an IAT sensor for reference against voltage.

I’m sure that if these sensors are ultra delicate, they could be easily damaged whilst being swapped over into the new intake/pipework. I would have thought that a slight knock or touch could potentially throw them out of whack. Not saying at all that people haven’t been ultra careful when swapping these over but i can’t imagine these MAF sensors are robust.

OEM MAF part number - 22204-75040

Not cheap mind!
 
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