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Old Mar 25, 2018 | 03:18 PM
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Default Hesitation problem

hi everyone when I'm driving my car hard and out my foot flat down the pull off ect is all fine but when I get to around 4.5 k revs it basically starts to drive like a non turbo but if I lift my foot of then ease the power on it will happily continue to boost all the way up any ideas what could be causeing this problem please I have a w reg classic uk2000 wrx I do have some mods and as far as I can tell I have no boost leaks as my gauge holds firm at 0.8 any help or advice would be great thanks
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Old Mar 25, 2018 | 03:48 PM
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From: Rl'yeh
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It would help us to know what mods you have and if they have been mapped?

Have you changed plugs recently? On my first change done at the dealers, they damaged a plug lead, which gave hesitation at 4500rpm.
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Old Mar 25, 2018 | 05:30 PM
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Originally Posted by alcazar
It would help us to know what mods you have and if they have been mapped?

Have you changed plugs recently? On my first change done at the dealers, they damaged a plug lead, which gave hesitation at 4500rpm.
i haven't don't plugs no but that is what I am planing on doing in the next week or so
I have front mount intercooler fitted 255 fuel pump 3" straight through system open bell mouth induction kit bigger intake pipe dump valve can't think what else atm but I did have the problem before half of that was fitted aswell
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Old Mar 25, 2018 | 05:40 PM
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Full decat,fmic,bigger intake.
Still running standard map.
You will not only be feeling lag but I can guarantee you will be running lean and detting.
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Old Mar 25, 2018 | 06:14 PM
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Originally Posted by ossett2k2
Full decat,fmic,bigger intake.
Still running standard map.
You will not only be feeling lag but I can guarantee you will be running lean and detting.
most probably mate I've got a bigger turbo to go on aswell just getting it all serviced new plugs ect sorted and then want to sort this issue aswell before get mapped as I said in the reply was doing before I fitted half of the parts fort wasn't getting enugth fuel that's why I fitted the bigger pump ect already :/
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Old Mar 25, 2018 | 06:32 PM
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Which half of the mods did you fit when it started running crap?
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Old Mar 25, 2018 | 06:36 PM
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To be honest I never really gave it the beans when I first got it and the only mods I had when I first noticed the problem was a induction kit and back box and intercooler but it boosts up fine then feels like it hits a wall but then if I take foot of and ease on it is fine
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Old Mar 25, 2018 | 09:10 PM
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From: Rl'yeh
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Don't give it any more beans until you've had the map looked at.

Trust me, detting kills the engine and it's bl**dy expensive failure.
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Old Mar 26, 2018 | 10:05 AM
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Originally Posted by alcazar
Don't give it any more beans until you've had the map looked at.

Trust me, detting kills the engine and it's bl**dy expensive failure.
if it is detinating like you say what would it be doing ?
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Old Mar 26, 2018 | 11:10 AM
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From: Rl'yeh
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You will be doing well to hear, or sense anything.
Basically it's running lean, which leads the fuel/air mixture to explode in the cylinder well BEFORE the piston reaches tdc. This obviously causes a massive shock to the piston, rods and bearings/crank, since the piston is trying to move upwards and the explosion is trying to move it back down. The usual result is that the main bearings destroy themselves, loss of oil pressure etc. That's your engine needing rebuilt, right there.

I've also seen reports or melted pistons, broken valves and headgasket failure.

Trust me, these engines do NOT like you messing with the air/fuel ratio unless you alter the map to suit. And putting cone filters on, FMIC etc is messing with the air/fuel ratio big time.
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Old Mar 26, 2018 | 09:00 PM
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+1 above,messing.
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Old Mar 27, 2018 | 03:42 PM
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Do you think I would be best to take it to a rolling road to try and diagnose the problem I plan to have xmcar mapped end of next month or the following month I don't use the car all the time just want it to be right before fit my other bits and get it mapped
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Old Mar 29, 2018 | 03:30 PM
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It's not going to be right! Until you've had it remapped .
you either have to get it remapped now with parts you have fitted or stop driving it. or fit everything else now and stop driving it until you get it remapped.
if you carry on fitting parts and driving it ,as said above it will cause damage.
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Old Mar 29, 2018 | 04:01 PM
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car needs remapping, simple as that.
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