GR Yaris New air intake fitted, overboost error

Thanks for the link to ‘the other place’ @AK10TOY, I never really venture there & found that thread an interesting read!

It seems to me that the end product wasn’t as good quality out the door as I was hoping it would be. I find it hard to believe that the lip on the MAF housing, where it is bonded to the airbox, is the cause of the issues though. The volume of air entering the MAF tube remains the same. Maybe it causes excessive turbulence too close to the MAF sensor & the ECU shits itself? 🤔
(Ingesting more air than the expected value measured/calculated by the MAF)

It’s good to see Adriano Piras is sending out a complete replacement MAF-side of the airbox to affected customers though.

Have you put your OEM intake back on for the time being?
 
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Suppose I'll find out when I fit the new rear section,

the previous set up is going back on Today hopefully after work, to rule out any other issues before I try the new rear section of the Piras airbox,
 
AK10TOY said:
Suppose I'll find out when I fit the new rear section,

the previous set up is going back on Today hopefully after work, to rule out any other issues before I try the new rear section of the Piras airbox,
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Fingers crossed!
 
Every time I see someone building an aftermarket intake system and relocating the MAF sensor to a new pipe, claiming everything’s fine, it honestly makes me cringe. Pipe diameter is only part of the equation. The flow profile, laminar flow versus turbulence in different parts of the cross-section, is just as important.
The MAF sensor doesn’t measure airflow across the whole pipe, it only samples a small area. And the ECU is calibrated based on the airflow characteristics in that exact spot. A new intake pipe can have a completely different flow profile. Even if the flow is more laminar across the entire cross-section, that doesn’t automatically make it better. At least not without proper ECU tuning.
And I don't care if it's a nice and shiny Eventuri that flows more air and makes more power, it’s still skewing the MAF readings. That means the ECU’s not getting the right data, and engine control won’t be as precise as with the stock intake system.
 
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tonic said:
Every time I see someone building an aftermarket intake system and relocating the MAF sensor to a new pipe, claiming everything’s fine, it honestly makes me cringe. Pipe diameter is only part of the equation. The flow profile, laminar flow versus turbulence in different parts of the cross-section, is just as important.
The MAF sensor doesn’t measure airflow across the whole pipe; it only samples a small area. And the ECU is calibrated based on the airflow characteristics in that exact spot. A new intake pipe can have a completely different flow profile. Even if the flow is more laminar across the entire cross-section, that doesn’t automatically make it better. At least not without proper ECU tuning.
And I don't care if it's a nice and shiny Eventuri that flows more air and makes more power, it’s still skewing the MAF readings. That means the ECU’s not getting the right data, and engine control won’t be as precise as with the stock intake system.
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Cant disagree with anything there really

There's plenty of intakes out there that work fine without having to tune the car however, which mine isn't yet, just a few bolt on mods, it was claimed this was one of them, all I was looking for was something with abit more noise and OEM filter,

I'm very sceptical of the power claims some people make about intakes when probably all are done with a fan in front of the car if that, that isn't real air flow.
 
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GRavy_Baby said:
Have you put your OEM intake back on for the time being?
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It's been put back on and runs perfectly fine as it was

Went for a drive for an hour, revved freely to redline throughout gears, whereas before it would give the reduced engine power warning at about 6k revs when WOT in 2nd and 3rd, rules out anything else other than the airbox at least.
 
AK10TOY said:
It's been put back on and runs perfectly fine as it was

Went for a drive for an hour, revved freely to redline throughout gears, whereas before it would give the reduced engine power warning at about 6k revs when WOT in 2nd and 3rd, rules out anything else other than the airbox at least.
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That’s great news although tinged with slight disappointment mate. Bitter sweet & confirms the MAF housing on the Piras unit is unsatisfactory. Hopefully he comes through & irons out the problem, although it seems too quickly turned around from a manufacturing point of view. The OEM MAF sensor /ECU sure is fussy but as @tonic has put it, why mess with the recipe when the ECU doesn’t take any old reading. Clever that the ECU is so finely calibrated to be fair.
 
like i said days ago........ be the maf position or spacing of it. I've also seen reports of this intake being poorly made, bonding / glue, turbo side after the filter looks shocking and quite frankly scary! I make no excuses for people producing tat and taking hard earned money out of peoples pockets.

Iam slightly biased though as my opinion of the seller is that he is full of s**t and basically a con man.
 
tonic said:
Every time I see someone building an aftermarket intake system and relocating the MAF sensor to a new pipe, claiming everything’s fine, it honestly makes me cringe. Pipe diameter is only part of the equation. The flow profile, laminar flow versus turbulence in different parts of the cross-section, is just as important.
The MAF sensor doesn’t measure airflow across the whole pipe, it only samples a small area. And the ECU is calibrated based on the airflow characteristics in that exact spot. A new intake pipe can have a completely different flow profile. Even if the flow is more laminar across the entire cross-section, that doesn’t automatically make it better. At least not without proper ECU tuning.
And I don't care if it's a nice and shiny Eventuri that flows more air and makes more power, it’s still skewing the MAF readings. That means the ECU’s not getting the right data, and engine control won’t be as precise as with the stock intake system.
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It's the first thing I think about whenever I see an intake with a different MAF tube or airbox entrance to the MAF tube... MAF scaling is now incorrect :)

I even remember way back in the day when HKS sold piggyback electronic idle stabilizer for the JZX100 1JZ because if you even added a "suction kit" which is between the MAF sensor and turbo, it would cause the car to die when pushing the clutch in when coming to a stop...
 
I realise to everyone this may seem like a silly idea, but if the issue persists would it not be worth putting something in the duct to smooth the airflow?
 
Ecsrobin said:
The solution would be to fit an intake that works?
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Well yes quite, but given it doesn't, I am wondering if a slight mod would help? And, to be fair, how many do work? Reading stuff out there, you have the standard Toyota one and if you are looking for improvement the Eventuri one?
 
speeddemon666 said:
Well yes quite, but given it doesn't, I am wondering if a slight mod would help? And, to be fair, how many do work? Reading stuff out there, you have the standard Toyota one and if you are looking for improvement the Eventuri one?
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Yeah I get where you’re coming from but when you’ve paid good money for something that claims to work it should work and not require you to spend time or energy on bodging it.

I run Eventuri.
 
Ecsrobin said:
Yeah I get where you’re coming from but when you’ve paid good money for something that claims to work it should work and not require you to spend time or energy on bodging it.

I run Eventuri.
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I agree, I think I would be less than unhappy. Doubtless I will get one of those myself.
 
Chris_P_Bacon said:
fixed it yet?
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No reason to fix, it worked from beginning. Standard air filter insert. All parts were ok for me, fitting the MAF was intuitive (just be sure it goes in completely and then turn it against the nose before tightening the screws). Be sure there is no air leakage and block the hose to the now unused flap. In addition (and to be sure) electrically disconnect the unused magnetic flap. Until now over about 500 km on streets no reduced power or check engine, fully compatible to DTUK stage 2.

Adriano already announced, that he will exchange not fully bonded items. I was lucky, all worked from start. I like the sound and the subjectively improved air flow.

Bye for now Fred
 
I wasn't happy but why not give them a chance to redeem themselves? If I get the same issue with the replacement part, it'll get returned.

The thread was about my issue since fitting the airbox, not people's personal opinions of the bloke.

I agree with what @Ecsrobin said, I don't think anyone should really be having to bodge something, stock top airbox with 3d printed scoop and lower box works fine and is back on for now.

I'd also add if people don't have something constructive to add to the discussion then why bother replying 🤷‍♂️.
 
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AP756 said:
No reason to fix, it worked from beginning. Standard air filter insert. All parts were ok for me, fitting the MAF was intuitive (just be sure it goes in completely and then turn it against the nose before tightening the screws). Be sure there is no air leakage and block the hose to the now unused flap. In addition (and to be sure) electrically disconnect the unused magnetic flap. Until now over about 500 km on streets no reduced power or check engine, fully compatible to DTUK stage 2.

Adriano already announced, that he will exchange not fully bonded items. I was lucky, all worked from start. I like the sound and the subjectively improved air flow.

Bye for now Fred
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My car is stock apart from bolt on mods of exhaust, IC and forge turbo inlet.

I checked for leakage before removing the Piras airbox, still had the same issue on the next test drive, putting the stock airbox back, the car ran perfectly fine. The solenoid/vacuum hose, for the flap is irrelevant as it was already plugged due to having Helmut's 3d printed scoop and lower box.

Happy yours works fine, Hopefully the replacement part solves my issue.
 
AP756 said:
No reason to fix, it worked from beginning. Standard air filter insert. All parts were ok for me, fitting the MAF was intuitive (just be sure it goes in completely and then turn it against the nose before tightening the screws). Be sure there is no air leakage and block the hose to the now unused flap. In addition (and to be sure) electrically disconnect the unused magnetic flap. Until now over about 500 km on streets no reduced power or check engine, fully compatible to DTUK stage 2.

Adriano already announced, that he will exchange not fully bonded items. I was lucky, all worked from start. I like the sound and the subjectively improved air flow.

Bye for now Fred
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I wasn't asking you. I was asking the OP if he had fixed his problems after fitting.
 
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