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*waves*
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I ran my MR2 on an ST205 ECU for ages.
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If you've seen the side-by-side comparison rolling road print outs between the two ECUs, they were probably mine.
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You only need to disconnect one of the two PS pins but I can never remember which one
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- but you've already worked that out!
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The INT pin replaces the FAN pin, so you lose your connection from the ECU to the engine bay fan controller.
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This is no big deal
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- the fan controller runs autonomously.
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Some of the pins used for pump monitoring
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(M+, M- and MTT) I think overlap with pins that are identified as part of the interface between the MR2 ECU and the
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(optional) traction control ECU.
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As I've never played with an MR2 with TRC and only actually know of one person with rev3+ TRC, this never bothered me.
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You can't use the chargecooler and the Toyota TRC together for another reason anyway
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- the TRC incorporates a 2nd throttlebody with its own throttle position sensor which would encroach into the space the core fits in.
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I rebuilt my pump loom using resistive wire rather than inline resistors as it is from the factory
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- the ancient resistors had crumbled to pieces and I thought resistive wire coated in heatshrink would be a bit more weatherproof.
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The ST205 aircon setup is identical, but the power steering pump has an additional idle up valve on it which is another difference between the two ECUs.
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Oh and just to check, you are using a JDM ST205 ECU, right? Otherwise you'll lose power!
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I know of someone else who's since done this ECU conversion
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(also on a cari blue rev3!) who didn't have the idle speed problems I encountered.
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I'm interested to hear how your car idles once the weather has improved a bit.
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RST wrote:There must be an easier way, the CC pump in my ST205 WRC I just bought comes in at about 1,000rpm then waits about 30s then stops.
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If I recall the a'PEXI RSM I had years ago and simlar devices have PnP's
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(or NpN's) which can be set to various trigger limits, if you use something like that via a relay then you will have something very similar and simple wiring?
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Then there'd be no mucking about with the car's wiring with similar end effect?
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Changing the ECU is the right way to do it IMO, if your intention is to run the chargecooler and retain stock Toyota management.
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The pump doesn't kick in at 1000rpm, otherwise it would be on constantly at cold idle.
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There's more logic behind it than that
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(it's throttle driven not rpm driven for starters).
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Combine that with warning lights for low coolant level and pump failure, a measurable power increase and a tangible effect in engine smoothness, it's pretty good for
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£50.
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