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Old 07-22-2012, 04:54 PM   #26
cdoliver
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Quote:
Originally Posted by MADMIKE874 View Post
I just spoke with one of the guys from rallysport and I told him my issues and asked about the the same FPR you mentioned wanting to know if he thought that would fix it and he thinks it is some thing else. His thoughts were if it were the FPR it would have shown on the dyno tune. He said it sounds simpler than that like a leak or a hose loose. So I guess once I get it back together it do another pressure test.
that was my first guess in your situation, but you said you checked for leaks. let me ask you this:

Does it stutter at WOT? or just partial throttle?
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Old 07-22-2012, 06:09 PM   #27
MADMIKE874
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At any throttle it does it, if I'm slow on the gas or full throttle as soon as it hits 2700 rpm it like hits a wall and struggle all way to 3000 then it is fine pulls hard
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Old 07-22-2012, 06:32 PM   #28
cdoliver
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At any throttle it does it, if I'm slow on the gas or full throttle as soon as it hits 2700 rpm it like hits a wall and struggle all way to 3000 then it is fine pulls hard
Then I would say you have a different problem than the OP then. His problem is only partial throttle. you have a hose that has come off or a physical problem.
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Old 07-23-2012, 05:32 AM   #29
konsept
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Then I would say you have a different problem than the OP then. His problem is only partial throttle. you have a hose that has come off or a physical problem.
When I'm WOT the car will rev freely until 2800rpms... then it'll "slam a wall" where as I described it as the nose of my car dropping completely as if I had just pressed the clutch pedal in... but it'll hesitate for a second then carry on... the hesitation gets more noticeable and longer to overcome in 4th-6th gear, where 6th gear being the most noticeable and longest to pass through... once it's gotten past 3000 rpms, it'll just rocket forward.

In short: same issue I have.
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Old 07-23-2012, 11:07 AM   #30
MADMIKE874
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Exactly what mines does, you can take off from a stop at WOT but as soon as you hit 2700 rpm it like you said hits a wall and struggels really hard to get past 3000 but when It finally does it flat out moves. And it does get much worse and more noticeable in higher gears. But if you are just driving normal and shifting before much boost kicks in you are always in that rpm rang no matter what gear you are in which is basically a pain in the @$$ the whole time
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Old 07-23-2012, 03:38 PM   #31
ByeBye4g63t
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I had the same problem as OP. One of the plugs on my injector harness backed out, and there was a loose connection on cylinder 3. Was getting a misfire and was running really lean. Check all your connections to the injectors, and try swapping coil packs to see if the code follows.
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Old 07-23-2012, 06:03 PM   #32
MADMIKE874
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I could see that as maybe an issue as I am using the injectors dynamic 1000cc injectors with the plug and play adaptors, which are rather long which made tucking them away a bit difficult maybe they don't have a good connection. But probably not until after I try the few other things first as getting to injectors is a job I don't really wanna do again
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Old 07-24-2012, 10:10 PM   #33
cdoliver
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also could be a bad front o2 sensor
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Old 07-31-2012, 01:12 AM   #34
IA Performance
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We've seen the same hesitation issues over the years and the FPR makes a night and day difference from a tuning stand point. I'd say the mechanical fix takes care of 65% of the problem, the remaining is 35% tuning.

I tuned a 2012 the other weekend and the end result was butter smooth at any throttle position and load. It takes time and the right parts. i'm not perfect, and I'm sure there will be cars that win the battle, but i'm willing to fight to the finish.

Car mods:
2012 STi
FIC 1100cc
91 and also e85
TBE
CAI
Fuel Dampener kit

We offer a kit that uses OE Subaru parts, quite easy to install too:


stephen@iaperformance.com
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Old 08-01-2012, 08:33 PM   #35
MADMIKE874
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Well we got the headers coated and on, we got the intocooler pipes swapped around and it made a dramatic difference with the heat. Everything was much cooler. But after changing the headers the issue got worse. So we thought for a minute and realized that we increased the flow to the Turbo and it got worse. It was having a major fuel issue and a major back pressure issue. Then it clicked, the down pipe, I was running a full perrin exhaust Turbo back with a high flow cat. Which we are guessing went bad with the extream heat we had.

Well at this point I'm out of money and out of patience, so my wife being the amazing person she is steps up and runs down to rallysport and picks me up a new catless invidia down pipe. Which we swapped out, the put back on the dyno, and guess what after a little tuning problem solved.

I'm sure this is not going to be the same fix for many if any one but something to consider. Go catless all the way.
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Old 08-02-2012, 06:21 PM   #36
threelete
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Quote:
Originally Posted by MADMIKE874 View Post
I just spoke with one of the guys from rallysport and I told him my issues and asked about the the same FPR you mentioned wanting to know if he thought that would fix it and he thinks it is some thing else. His thoughts were if it were the FPR it would have shown on the dyno tune. He said it sounds simpler than that like a leak or a hose loose. So I guess once I get it back together it do another pressure test.
Yes!!! i think it's your fuel line coming off your fuel pump. My fuel line kept slipping off the connection after installing a couple different fuel pumps. Topspeed wired mine back around the plastic toggle on the plastic body of the fuel pump "holder". Sorry, I don't know the technical name of this white factory piece that holds the fuel pump. I think this is a real issue. My hesitation is basically gone, but not 100% gone. Only feel it under light throttle under 2800rpms and very rarely feel it.
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Old 08-07-2012, 02:08 PM   #37
konsept
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The Aeromotive FPR has arrived. Scheduling a time with the mechanic to have it installed.

Hoping to have positive updates by next week. Fingers crossed!
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Old 09-07-2012, 09:46 PM   #38
nmlittlebigman
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You might also check out this thread if your problem is hesitation or "stumble" between 2,000 to 3,000 rpms under low load. It references a kit make by Goodspeed which sells for around $ 80. In a nutshell the kit eliminates the balance hose and converts the system from series to parallel. (I will be ordering mine soon).
http://forums.nasioc.com/forums/show...ht=fpr+stumble
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