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AFR only 11.4 because exhaust leak?

Based

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#1
Ok so I recently changed my exhaust. After putting my new exhaust on my AFR went from steady 12.2 at WOT to 11.37. They hit 12.0 then go down as RPM go up. This didn't happen before.

I reused the stock gasket... Could this be the reason for an exhaust leak? Or maybe I didn't use the exhaust clamps correctly?
 


Hijinx

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#2
11.4 is richer than 12.2.

What did you change? Your downpipe?


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Based

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Thread Starter #3
11.4 is richer than 12.2.

What did you change? Your downpipe?


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Yeah I know it's richer that's why I think I either have a exhaust leak or for some reason I'm leaking boost or something.

I just changed the catback.

But for a week I was open downpipe and I noticed the AFR being different then. But I thought once I put my exhaust on it would go back to normal but nothing's changed. And lack of low end punch.
 


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Based

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Thread Starter #4
11.4 is richer than 12.2.

What did you change? Your downpipe?


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Yeah I know it's richer that's why I think I either have a exhaust leak or for some reason I'm leaking boost or something.

I just changed the catback.

But for a week I was open downpipe and I noticed the AFR being different then. But I thought once I put my exhaust on it would go back to normal but nothing's changed. And lack of low end punch.
 


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corpus christi
#5
I could be wrong, but the ecu may have made adjustments for that week while your exhaust was off. Idk if unhooking your battery for a little bit will reset it but it wont hurt to try.
 


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Based

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Thread Starter #6
I could be wrong, but the ecu may have made adjustments for that week while your exhaust was off. Idk if unhooking your battery for a little bit will reset it but it wont hurt to try.
That sounds reasonable but I've been driving for maybe 3 hours on this new tune and it hasn't learned anything. I would assume if it could adapt to my open downpipe it could adapt to my new tune and mods.

My fuel rail pressure is 2200 at WOT with my AFR at 11.4. I'm definitely running rich. I just now checked for boost leaks and I didn't see any loose hoses.


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#9
I looked at it. The highest boost you hit was 23.17 with an afr of 11.91, which is fine. The tune you bought is ots it is meant to be conservative and caters to a lot of different climates and environments. My first suggestion would be to recheck your charge pipes, I would then look at your vacuum lines off of the turbo, and one off of the cold side charge pipe, also double check the lines off of your intake. if everything looks good. I would either try to reset kam on your accesport or I would reflash the map. Boost is based off of torque targets this car will only boost whatever it needs to see that torque target, this depends on the weather outside, the colder the air the less boost you will see because the air is more dense and it doesn't need big boost to hit that target. I would honestly say as well as long as your afrs aren't dropping down to Low 10s or going to 13s at wot you're fine. I remember on my stratified ots tune I would periodically hit 10.88 at wot.
 


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Thread Starter #10
I looked at it. The highest boost you hit was 23.17 with an afr of 11.91, which is fine. The tune you bought is ots it is meant to be conservative and caters to a lot of different climates and environments. My first suggestion would be to recheck your charge pipes, I would then look at your vacuum lines off of the turbo, and one off of the cold side charge pipe, also double check the lines off of your intake. if everything looks good. I would either try to reset kam on your accesport or I would reflash the map. Boost is based off of torque targets this car will only boost whatever it needs to see that torque target, this depends on the weather outside, the colder the air the less boost you will see because the air is more dense and it doesn't need big boost to hit that target. I would honestly say as well as long as your afrs aren't dropping down to Low 10s or going to 13s at wot you're fine. I remember on my stratified ots tune I would periodically hit 10.88 at wot.
Oh ok. I'm on a flash tune from stratified right now with a Depo racing intercooler and Borla catback. It's just that my car feels almost the same as it did stock even now that I have my intercooler.


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#11
The catback did nothing for you but enhance sound. the intercooler doesn't gain you anything, it just allows you to not lose hp that you would from heat soak pull after pull, keeps power consistent. stratified can only pull so much out of your car due to safety reasons, if you were to do a data log refinement they can pull a little bit more out of your car due to them knowing how it's reacting in its environment. If you can throw up a wot 3rd gear pull or 4th gear pull on vdyno I can show you what numbers you should be hitting around, that is if you're running 93 I'll post here in a second

 


Hijinx

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#12
Yeah I know it's richer that's why I think I either have a exhaust leak or for some reason I'm leaking boost or something.

I just changed the catback.

But for a week I was open downpipe and I noticed the AFR being different then. But I thought once I put my exhaust on it would go back to normal but nothing's changed. And lack of low end punch.
You wouldn't see a rich condition unless the leak was before the o2 sensors... They don't care about what's after them because they can't sense it.

I'm having trouble understanding this timeline. This is what I've got so far:

You were 12.2 at WOT.

Removed cat back, still 12.2

Installed Strat OTS, now 11.xx

Installed cat back, still 11.xx

If that's the timeline... It's tune related, not hardware.


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Based

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Thread Starter #13
You wouldn't see a rich condition unless the leak was before the o2 sensors... They don't care about what's after them because they can't sense it.

I'm having trouble understanding this timeline. This is what I've got so far:

You were 12.2 at WOT.

Removed cat back, still 12.2

Installed Strat OTS, now 11.xx

Installed cat back, still 11.xx

If that's the timeline... It's tune related, not hardware.


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Ok yeah sorry I was being a little confusing. This is the timeline:

Stock car with tune - 12.2
Took catback off but keep same tune - 11.x
Put new catback on and intercooler - still 11.x
Get new tune - still same speed and 11.x AFR

I just expected to be faster now that I have an intercooler. Maybe it's just because the temperature down here jumped up 15 degrees in the past week.



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Hijinx

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#14
Ok yeah sorry I was being a little confusing. This is the timeline:

Stock car with tune - 12.2
Took catback off but keep same tune - 11.x
Put new catback on and intercooler - still 11.x
Get new tune - still same speed and 11.x AFR

I just expected to be faster now that I have an intercooler. Maybe it's just because the temperature down here jumped up 15 degrees in the past week.



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My next question was going to be the temperature. That's probably the culprit. Colder air requires more fuel, so running a little leaner was taking advantage of the cooler air. Now that it's warmer, you're not getting the same effect.


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#15
Ok now it makes more sense! If its in the 11s WOT on an OTS tune, then its the tune im pretty sure. Im on an unrevised stage 2 map from mountune and just did a pull to look at the afr and guess what, it was 11.47 on the top end lol. Also after installing my intercooler and the tune, it didnt feel any faster, and almost has a tiny bit more boost threshold because its filling up a larger volume of air.
 


OP
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Alright I'm definitely leaking boost. My car is slower than it was when I bought it. It peaks boost at like 3500 at 24psi then falls off to like 16psi at 5500 rpm. I'm gonna check the hose clamps tomorrow I guess.


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#17
it's supposed to, you won't be able to hold more then 14psi of boost all the way to redline. the only thing you can do is buy a turbosmart wastegate actuator, but then you're going to need a protune.
 


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it's supposed to, you won't be able to hold more then 14psi of boost all the way to redline. the only thing you can do is buy a turbosmart wastegate actuator, but then you're going to need a protune.
It just feels a lot slower than it did like a month ago though. Idk what it is


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#20
Get that protune upgrade from Stratified amd youll be back on track. Everything is fine as far a boost dropping on stock turbo. How you feel is how i felt when i threw on an intercooler with a cobb OTS. It was slow as shit, so i immediately got in touch with Mountune for a new tune, then all was back to normal.
 


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