Is it possible that due to your dirty fuel filter, that some dirt has infact got through to your injector(s) and one or some of them may be clogged?

If that is a possibility, you may wanna just buy 4 brand new ones to be sure?

Other than that .. I've heard a good way to fuck up someones car is put a plastic bag or three in someones fuel tank.

They break down, get past the filter and fuck the motor somethin wicked .. Or so i've heard .. :P

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[SIGPIC][/SIGPIC]
Should have bought an STI

about the TPS one way to check it is using a multimetre than can have a graph and slowly press accelerator to see the gradual climb on the graph. If there is a dip/break then that could be your problem. I recon its the computer though. Or since it was fixed for a while when you did the filter maybe the fuel tank is full of crap and its just filling filter and pump with that again, have had that a few times at work it is surprising the crap you find in the tank

Yes Anton

In the fully closed postion it should read somewhere between 0.2-0.8 volts DC
STD around 0.5.

In the fully open position 4.0-4.6 volts DC.

The readings from closed to fully open should be linear with no flat spots as a gradual climb as you said.
Therefore sending correct voltages back to the ECU.
If there are intimittant voltages going back, the ECU wont Know wether its comming or going, fuel mixes injector timming, ect , ect is all up the S%*T.

Update:
Looks like its an electrical problem rather than a fuel problem as mentioned earlier in this thread. Just talked to the workshop, they had an auto-electrician look at it and he seems to be 99% certain its the coils/igniter (he had a similar problem in his old car).

I got my unichip removed and it drives better with the stock ecu now they reckon and the major stuttering is gone, however some misfiring still occurs which should hopefully be sorted with the electric stuff fixed.

One minor concern of mine was if the unichip was removed, will i need to re-tune the stock ecu? And will it affect my boost controller (goes up to 1.2bar i think) at all?

turn your boost back down to stock or at least near stock. Standard ecu should be fine now the unichip is gone.
Have you checked your leads to see if they are arking out in the spark plug holes

The new Lancer Evolution IX FQ360 is comig out soon. 0-100 times in under 4 seconds from factory! Thought about upgrading?

Yeah yeah I know grill me over it but the truth is with the FQ360 and Evo X about to hit Australia, Subaru (us) have a challenge ahead of us.

give me money and ill upgrade. wtf does that have to do with my thread? anyway because u bumped it ill update. problem has been solved. unichip removed, ran alot better but still some misfiring. checked spark plugs, even tho they were brand new they were the wrong type (used for n/a subarus) apparantly the place that did the 100k service fucked it up. so yeah cars all good now u can lock the thread.

Still be cheaper than a new engine dude.

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