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Old 10-20-2017, 11:37 AM   #1
KPHTH WRX
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Default 08 WRX power loss on switch from Stage 1 to Stage 2

Original owner of my 08 WRX (purchased 10/07), currently 95k miles. Stock TD04 Turbo.

For many years I ran the Torqued Performance Stage 1 Map with AEM CAI and was very happy with the result. I have the Torque App to keep track of Boost, HP/Torque, 0-60 #s, etc. After my stage 1 flash, I would consistently see HP/TQ in the 240/240 range on strong pulls with a TON of power coming in the low end around 3K RPM especially in 2nd/3rd gear.

It was recently time for a clutch replacement, so in addition, I upgraded to an Nvidia Catless DP, Grimmspeed Boost Solenoid, and Turbosmart Recirc valve + Dyno/Pro Tune. Still on factory CB exhaust.

To put it bluntly, I'm less than happy with how my car drives. Power on the Torqued app is maxing at 200HP and 225tq, I have NO low end torque, and my car has heavy exhaust smell. (From DP I know).

Is this a classic case of boost leak? Is my setup just garbage? Will a VF52 remedy the issue? For one day after the dyno tune, I felt I was seeing highers numbers on the App... and the butt dyno... .but not anymore.

Thoughts?
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Old 10-20-2017, 01:25 PM   #2
relative4
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You need to take this back to your tuner.
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Old 10-20-2017, 02:19 PM   #3
Charlie-III
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Quote:
Originally Posted by relative4 View Post
You need to take this back to your tuner.
Agreed.
Some Subaru are OK with a CATlessDP, others need a serious tune.

Talk to your tuner, likely way better than the internet.
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Old 10-20-2017, 03:06 PM   #4
KPHTH WRX
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The tuner initially wants to blame it on a bad clutch... which he just upgraded to Exedy Stage 1 @ 5k miles ago. Going back for a smoke test tomorrow AM. Thanks for the feedback.

In reality, what would cause power loss in the 50-90HP/TQ range? I'm reading the Throttlebody hose/clamp is a common culprit (if it is indeed a leak). It can't be that complicated!?!?

Last edited by KPHTH WRX; 10-20-2017 at 03:20 PM.
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Old 10-20-2017, 03:37 PM   #5
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It can be quite complicated. Or quite simple. The possible causes approach infinity. Analyzing logs will point a qualified tuner to likely culprits, for which tests should be run. Not sure how a bad clutch takes one to a smoke test.
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Old 10-20-2017, 03:44 PM   #6
KPHTH WRX
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Quote:
Originally Posted by relative4 View Post
It can be quite complicated. Or quite simple. The possible causes approach infinity. Analyzing logs will point a qualified tuner to likely culprits, for which tests should be run. Not sure how a bad clutch takes one to a smoke test.
To clarify, I'm claiming boost leak, he think it's the clutch. We're doing the smoke test to verify if it's leak or not.

No slipping from clutch at all, not saying that it's not that, but highly unlikely.
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Old 10-20-2017, 07:46 PM   #7
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Go back to Torqued Performance.
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Old 10-21-2017, 03:16 AM   #8
josethewoe
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Quote:
Originally Posted by KPHTH WRX View Post
To clarify, I'm claiming boost leak, he think it's the clutch. We're doing the smoke test to verify if it's leak or not.

No slipping from clutch at all, not saying that it's not that, but highly unlikely.
It’s definitely a boost leak. Upon removing your intercooler you probably either installed the throttle body wrong. Personally, because I’m having the same exact issue. I reinstalled it again and it fixed the leak, but as of 5 minutes ago while getting some logs done it popped off again thus I’m leaking again. I’m not sure if if the throttle body can’t handle the higher boost or the oem clamp just sucks that much.
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Old 10-21-2017, 11:23 AM   #9
KPHTH WRX
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Quote:
Originally Posted by josethewoe View Post
It’s definitely a boost leak. Upon removing your intercooler you probably either installed the throttle body wrong. Personally, because I’m having the same exact issue. I reinstalled it again and it fixed the leak, but as of 5 minutes ago while getting some logs done it popped off again thus I’m leaking again. I’m not sure if if the throttle body can’t handle the higher boost or the oem clamp just sucks that much.
I pulled my IC off last night to check the TB-IC hose/clamp.. and everything looked fine.

This morning went to the tuner and they ran the smoke test.. no leaks. Drove the car and he confirmed the clutch was good to go.... so no diagnosis.

That being said, I came home and pulled up TorquedPerformance and noticed my Stage I AEM CAI tune was set for 16.5 PSI boost. While test driving, I rarely noticed me over 14 PSI in gears 1-3 (spiking at 14.5 occasionally), only seeing higher boost in 4th gear.

I'm starting to think I have a very conservative & different tune vs TorquedPerformance and that may be the culprit. Thoughts?
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Old 10-21-2017, 11:54 AM   #10
relative4
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Well, definitely some stuff doesn't add up here. 16.5 PSI is a pretty high boost target for stage 1 with OEM downpipe. Maybe too high. 16.5 is a very typical boost target for stage 2. I would say the tune is hella weak, except did you say it was strong for a day or two? What is the boost target now?
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Old 10-21-2017, 02:48 PM   #11
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Quote:
Originally Posted by KPHTH WRX View Post
I pulled my IC off last night to check the TB-IC hose/clamp.. and everything looked fine.

This morning went to the tuner and they ran the smoke test.. no leaks. Drove the car and he confirmed the clutch was good to go.... so no diagnosis.

That being said, I came home and pulled up TorquedPerformance and noticed my Stage I AEM CAI tune was set for 16.5 PSI boost. While test driving, I rarely noticed me over 14 PSI in gears 1-3 (spiking at 14.5 occasionally), only seeing higher boost in 4th gear.

I'm starting to think I have a very conservative & different tune vs TorquedPerformance and that may be the culprit. Thoughts?
My target boost is 19, which I hot when I fixed the leak, but since the TB-IC keeps popping off I’m only hitting just abou 12. I’m stage 2 as well.
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Old 10-21-2017, 05:44 PM   #12
KPHTH WRX
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Going back on Tuesday for a reflash. We'll see what happens after that.
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Old 10-22-2017, 10:31 PM   #13
KPHTH WRX
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So odd turn of events last night. I performed an ECU reset, in addition to cleaning my MAF sensor, then decided to go for a drive. Using the Torque App, I was able to measure multiple pulls, 0-60mph, in the 5.002-5.033 sec range. I was boosting closer to 16psi, and seeing HP/TQ # in the 260HP/275FTLBS according to the app.

Previously, I couldn't clock one single run under 7 sec and HP/TQ #s were in the 200/210 range.

Could it have been as simple as this??

Last edited by KPHTH WRX; 10-23-2017 at 10:43 AM.
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Old 10-23-2017, 02:43 PM   #14
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Quote:
Originally Posted by KPHTH WRX View Post
So odd turn of events last night. I performed an ECU reset, in addition to cleaning my MAF sensor, then decided to go for a drive. Using the Torque App, I was able to measure multiple pulls, 0-60mph, in the 5.002-5.033 sec range. I was boosting closer to 16psi, and seeing HP/TQ # in the 260HP/275FTLBS according to the app.

Previously, I couldn't clock one single run under 7 sec and HP/TQ #s were in the 200/210 range.

Could it have been as simple as this??
Yes it could have, resetting the ECU allows it to learn the fuel trims from scratch.
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