Intake fitted S3.....down on power again!

-Ju-

-Ju-

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So a bit of background.
I have a 2009 S3 running stage 2 APR, milltek turbo back with sports cat and GFB dv+
On the standard airbox, which i've run for 6 months, it achieves an airflow of 250 g/s or 312bhp(roughly). I fitted a twintake and it dropped to 235 g/s (294bhp)
The feedback I got was to drop the Twintake as it was probably not playing with the APR software.
I've now got an ITG (the sealed one) and it still struggles to get 237 g/s or 296bhp. So roughly the same as the Twintake
I did have misfires with the Twintake at 6k rpm but not as yet with the ITG. I've also changed the plugs to no affect..
Do I need to reset the ECU for it to adapt properly and or should it relearn on its own?
 
Have you remapped for the new intake? any changes in set up requires a remap. You could be running lean, or rich now with the change in air flow.
 
APR recommend a CAI on stage 2 but you can run the standard airbox.
 
When you drive it does it feel down on power. The maf flow rates are only accurate when used with the stock intake. As the scaling of a Cai is different so will the peak g/s flow rates.
 
I have owned and mapped/had mapped many cars from S3's to Imprezas, and using standalone maps then making modifications to any part of the engine requires a remap. Its really that simple without going in to the boring technical reasons why :)
 
Dubjam said:
I have owned and mapped/had mapped many cars from S3's to Imprezas, and using standalone maps then making modifications to any part of the engine requires a remap. Its really that simple without going in to the boring technical reasons why :)
Click to expand...
Technically then a generic stage 2 APR map is mapped for the CAI so using it with the stock airbox should be a compromise!
 
audi upgrades
Tezgreig said:
When you drive it does it feel down on power. The maf flow rates are only accurate when used with the stock intake. As the scaling of a Cai is different so will the peak g/s flow rates.
Click to expand...
It still feels quick, but maybe not as quick top end.
So what you are saying is it could be flowing more air in reality but would need to be RR'd to confirm the BHP?
 
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Generic aftermarket maps are a ridiculous idea in my opinion, every engine and set up is different...and technically, you car is ******, so its obviously not right :)

I'd get it on the rollers with a good mapper to show you the problem and make adjustments.
 
3.2 Ju said:
It still feels quick, but maybe not as quick top end.
So what you are saying is it could be flowing more air in reality but would need to be RR'd to confirm the BHP?
Click to expand...

Yes exactly look at it this way imagine a gate 1 meter wide and 50 people to get through it in a second now a 2 meter gate same people to get through same time it won't be as congested so won't be moving as fast to move through it. But still the same amount of people through it hence why lower maf g/s readings. To make the most of your intake will need map tweaking or the car adapting to it for it to work better. Hope that makes sense and helps
 
As said above You can still have same or more power with a uppgraded CAI even if max MAF values are lower. Its not the software that is the problem here really, but a incorrect made maf housing size that t not matches the stock maf size. If the maf size is to big the air that passes maf sensor will go slower so you read lower maf values. and if the maf size is smaller then stock maf, the air will go faster over sensor and will read higher value. Yes you can adjust/scale this in software. but it should not be necessary! look at your fuel trims and check how they are with Vag com. block:032
 
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Tezgreig said:
Yes exactly look at it this way imagine a gate 1 meter wide and 50 people to get through it in a second now a 2 meter gate same people to get through same time it won't be as congested so won't be moving as fast to move through it. But still the same amount of people through it hence why lower maf g/s readings. To make the most of your intake will need map tweaking or the car adapting to it for it to work better. Hope that makes sense and helps
Click to expand...
Yeah I get that and I have heard that some of the Twintakes had the MAF housings slightly out in diameter, thats why they could give false readings.
However I thought the ITG, now redesigned as the VWR, where supposed to match the oem one so the Maf scaling was correct. APR use the VWR one and that is why I went with it.
 
Ice man said:
As said above You can still have same or more power with a uppgraded CAI even if max MAF values are lower. Its not the software that is the problem here really, but a incorrect made maf housing size that t not matches the stock maf size. If the maf size is to big the air that passes maf sensor will go slower so you read lower maf values. and if the maf size is smaller then stock maf, the air will go faster over sensor and will read higher value. Yes you can adjust/scale this in software. but it should not be necessary! look at your fuel trims and check how they are with Vag com. block:032
Click to expand...
I'll check the fuel trims later. Anyone done any Maf readings for comparison?
 
Understand. I know VWR also have had problems with incorrect maf values and ful trim. The latest revision shud be better. but still not correct. And i think APR no longer use VWR and support it for a reason.
 
Ice man said:
And i think APR no longer use VWR and support it for a reason.
Click to expand...

I think the reason there is more complex.

APR and VWR have had a "falling out" recently.
 
Yes you're right in that Alex!:) Before they stopped to cooperate i remember this 2.0TFSI VWR intake was big case especially in US.
 
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I'm having the same problem with a itg intake on stage 1, car runs much better on standard air box
 
All this talk about the oem airbox being restrictive, you would think any old pipe would be an improvement! lol
 
Yeah it's giving me a headache at the moment, seems to misfire and bog down with the itg on, also bought a new maf hoping it would solve the problem
 
Mine seems to run fine and is quick midrange, just top end it maybe struggles. I'm not sure if it'll adapt but i'll keep logging it and checking fuel trims.
Is yours open or sealed?
 
3.2 Ju said:
All this talk about the oem airbox being restrictive, you would think any old pipe would be an improvement! lol
Click to expand...

The OEM box works fine up to around Stg2.

After that,it's not good......there are gains to be had by replacing it at Stg1 and 2,but it will still work without causing misires.
 
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Open with ducting from fog grille to filter head, it has a good cold air supply, why would it misfire with intake fitted but not with standard air box
 
S3Alex said:
The OEM box works fine up to around Stg2.

After that,it's not good......there are gains to be had by replacing it at Stg1 and 2,but it will still work without causing misires.
Click to expand...
So if it is the intake again thats down on power/causing issues, can you recommend an intake for 2+, bearing in mind I would prefer sealed. Or would you think the ITG would be fine on 2+?
 
I use ithis intake! perfekt Fuel trim and maf values. TTRS airbox.TTS Air intake parts and custom alu maf house with stock sensor.

Sorry for the crappy Iphone picture!:dejection:
 

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3.2 Ju said:
So if it is the intake again thats down on power/causing issues, can you recommend an intake for 2+, bearing in mind I would prefer sealed. Or would you think the ITG would be fine on 2+?
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Any of the good intakes such as Revo,ITG,AMD etc will work fine.
 
Apart from the ITG I've got now lol
Think I'll try and throw this back towards APR.
I'm quite happy to keep the standard airbox if this ITG doesnt play ball, but if I go 2+, I have to have a CAI that works with the finicky software!
 
I would be surprised if its the intake causing this as the ITG is a popular and proven intake at power levels well in excess of the stage your at... The only way to work out what the problem is to do some data logging.
 
S3_Mat said:
I would be surprised if its the intake causing this as the ITG is a popular and proven intake at power levels well in excess of the stage your at... The only way to work out what the problem is to do some data logging.
Click to expand...
Which is why I ditched the Twintake in favour of the ITG. Apart from looks there isn't much love for the Twintake.
I can log the data fine, understanding it is another thing lol
 
3.2 Ju said:
Apart from the ITG I've got now lol
Think I'll try and throw this back towards APR.
I'm quite happy to keep the standard airbox if this ITG doesnt play ball, but if I go 2+, I have to have a CAI that works with the finicky software!
Click to expand...
I've got the original ITG which is no looker but effective.
 
Yeah I'm thinking this could be APR software and not actually intake related as such.
 
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That's a bit higher than recommended
Usually below 10 is the target.
The problem with buying a used intake is you never know how old it is, therefore you never know if it's pre or post modification.
The whole fuel trim issue was never really picked up until 2011-2012
 
I did a fuel trim check on my CTS Turbo intake and got 1.7 on short term trim value and flicking between +ve and -ve on long term trim using VCDS. I thought it might of been slightly higher but overall Im happy with what the result was.
 
Well its back off for now!
Not sure whether or not the ITG was actually revised, I know the VWR was but then that has a slightly different design.
This is the ITG
 
Got a revo intake on my stage 2 APR and havent had it misfire yet, might be because they prefer open cone as stated
 
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