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Hi, apologies if this has been covered but I'm well lost. 

 

Have bought a v5 Sti ecu to swap into my MY99 wrx hatch. I was lead to believe by the aussie wrx forums that this would swap in no worries, aside from having to swap two wires on the blue connector. 

 

The car runs and drives no worries after plugging it straight in, and swapping the pins over means it won't start. 

 

After this, the car will only boost to ~10psi and is now drinking fuel even worse than normal lol. 

 

Is there something I've missed? 

 

Markings on the board are A19-001 DS2 [N] 

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Please confirm - did you swap an STI ecu into a non-STI?

 

If yes, you need to change AFM and injectors as well at a minimum. You should also swap your turbo to the appropriately matched STI variant (likely a vf28) and run an STI intercooler.

You also need to make sure that the ECU you've swapped from was mapped for the same compression ratio as what you're swapping into as there are differences between some WRX and STI builds/years. E.g. some WRX were 9.0:1 yet the STI variant was 8.0:1 (or 8.5:1 - can't remember exact numbers but the point stands).

 

Someone else will be able to elaborate on this more than I can

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45 minutes ago, RaKid said:

Please confirm - did you swap an STI ecu into a non-STI?

 

If yes, you need to change AFM and injectors as well at a minimum. You should also swap your turbo to the appropriately matched STI variant (likely a vf28) and run an STI intercooler.

You also need to make sure that the ECU you've swapped from was mapped for the same compression ratio as what you're swapping into as there are differences between some WRX and STI builds/years. E.g. some WRX were 9.0:1 yet the STI variant was 8.0:1 (or 8.5:1 - can't remember exact numbers but the point stands).

 

Someone else will be able to elaborate on this more than I can

I did. 

 

From the brief reading I did about it, 99-00 wrxs had the same injectors and afm as the equivalent stis, but I could very well be wrong. I didn't see anything about compression ratios

 

Not fussed about getting it working, got the thing off a mate for $50 so thought why not? 

 

Cheers

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I have found an old CS thread on this type of ECU

Are you running a 2 or 3 port solenoid for the waste gate, if running a 2 port then that might be the issue as that ECU looks to need to use a 3 port

second page about half way down it talks about 3 port solenoid

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Ah that makes sense. Do you think this will be the only issue? If so could I just throw a boost tap I've got lying around in and wind it to 1 bar or will I be better off buying a 3 port? 

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as a starting point:

match the ecu and the afm

and potentially the sti turbo be a good idea

 

these ecu can be tuned so that allows a much better running car for NZ fuel

 

What part of the country are you in?

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@Pappu1What kind of afm am I after? The reading I've done suggests that wrx and Sti should be identical. 

I always run the thing on npd 100, is this still poorer than Japanese stuff? 

 

I'm in Marlborough 

 

Cheers

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That fuel should be good. 

I have also seen the afm being the same

in many threads.

i have the map for that so can compare.

i think the main difference might be the compression ration between the 207 and 205 engines and the sti being more aggressive in its setup. 

What turbo are u running? 

 

 

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The boost and timing tables are set for the the bigger sti turbo so the boost curves are set to hit different zones.

 

wat boost are you running

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On 18/01/2020 at 2:27 PM, RaKid said:

You should also swap your turbo to the appropriately matched STI variant (likely a vf28) and run an STI intercooler.

This, ECU will be trying to control the wrong sized turbo. The TDO4 is small compared to a VF28 type turbo.

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If the 205 is in good nick then just a remap of the stock ecu for the setup

should make it run nicer and safer and make better power. 

 

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