Help please, no acceleration after shifting into 5th during hard acceleration
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Car Info: 07 rs STi swapped Rotated BW S200SX-56
I have done a leak down test and it's solid. I have been told there is a fix for this with tuning. Will post up the results after I get to test it. Thanks for the idea though.
Same thing used to happen to me all the time, even when it was 20 degrees out (texas). Never figured out what it was since the motor was pulled a few weeks later for other reasons..let me know what your tuner says!
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Car Info: 07 rs STi swapped Rotated BW S200SX-56
Will do, I'm going to go back to the track and run it again after the adjustment to the tune. I'll post the results of how it runs and what he did if it cures the problem.
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Was any work performed on the vehicle just prior to the symptom occurring?
How long has the problem been occurring?
You say it happened at T-Hill?
When was that?
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This is the same shifting issue that has been around for a log time and is especially prevelent in the 06 ECU. It occurrs when boost stays above ~9psi between gears. The ECU responds by cutting fuel in the next gear until boost drops below the threshold. There are a couple fixes for this. Cobb's LC/FFS maps fix this issue and allow you to shift as quickly as you like without issue. Remember this only happens if the driver is shifting fast/hard enough as to not drop out of boost between gears.
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed
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Car Info: 07 rs STi swapped Rotated BW S200SX-56
June 1st was the first time I noticed it. I hadn't ran it hard since fall of last year. Since then I did a 6MT swap, went back to a TMIC, added a MBC, EL, & inlet. I had it tuned and it put down 290/321 to the wheels at 17.5-18psi. Car runs well and pulls to redline, it's just the transition into 5th gear that is giving me the fit. It is weird to me why it only happens in in the 4-5 shift. It is just as if I turned the ignition key off and then turned it back on.
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June 1st was the first time I noticed it. I hadn't ran it hard since fall of last year. Since then I did a 6MT swap, went back to a TMIC, added a MBC, EL, & inlet. I had it tuned and it put down 290/321 to the wheels at 17.5-18psi. Car runs well and pulls to redline, it's just the transition into 5th gear that is giving me the fit. It is weird to me why it only happens in in the 4-5 shift. It is just as if I turned the ignition key off and then turned it back on.
Obviously, with the hardware changes, it's safe to assume that the ECM calibration you were running last Fall was different than the current calibration.
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Car Info: 07 rs STi swapped Rotated BW S200SX-56
This is the same shifting issue that has been around for a log time and is especially prevelent in the 06 ECU. It occurrs when boost stays above ~9psi between gears. The ECU responds by cutting fuel in the next gear until boost drops below the threshold. There are a couple fixes for this. Cobb's LC/FFS maps fix this issue and allow you to shift as quickly as you like without issue. Remember this only happens if the driver is shifting fast/hard enough as to not drop out of boost between gears.
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed

Yeah, major changes. I bought the car with the FMIC setup, it had another tune in it done by the previous owner at another shop somewhere. I wanted to make it easier to pass smog, so I ditched the FMIC. I also broke the 5 speed on Christmas eve last year, so I did the 6MT swap. I never noticed it before, but I don't know what the tune was setup for either, one of the joys of purchasing a used modified car.
This is the same shifting issue that has been around for a log time and is especially prevelent in the 06 ECU. It occurrs when boost stays above ~9psi between gears. The ECU responds by cutting fuel in the next gear until boost drops below the threshold. There are a couple fixes for this. Cobb's LC/FFS maps fix this issue and allow you to shift as quickly as you like without issue. Remember this only happens if the driver is shifting fast/hard enough as to not drop out of boost between gears.
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed
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Thanks
-- Ed
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Car Info: 07 rs STi swapped Rotated BW S200SX-56
That sucks, 2 years? You don't get to take full advantage of your cars power with this problem. I know it doesn't affect us in everyday driving, it just makes it where you can't use it on the track very well when this happens.
But it should soon!
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This is the same shifting issue that has been around for a log time and is especially prevelent in the 06 ECU. It occurrs when boost stays above ~9psi between gears. The ECU responds by cutting fuel in the next gear until boost drops below the threshold. There are a couple fixes for this. Cobb's LC/FFS maps fix this issue and allow you to shift as quickly as you like without issue. Remember this only happens if the driver is shifting fast/hard enough as to not drop out of boost between gears.
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed
Derek, I'll get you your map with LC later today to try out.
Thanks
-- Ed
wholy crap my car has done this for the last 2 years and I learned to drive around the issue! thanks ed .. when I have it tuned again I will add the ffs to the map! even though I dont do it because im a little girl in a big skirt and I drive a forester.


