MRT Boost Cut Defender

Headlights to tailights and everything in between.

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Fkyx
Third Gear
Posts: 842
Joined: Fri Nov 02, 2007 5:30 am
Location: Albany, OR

MRT Boost Cut Defender

Post by Fkyx »

Contrary to its name, it's actually a fuel cut lifter. I found out mine was installed incorrectly, reading from the MAF, and not actually intercepting, even. So I'm looking to put it in it's proper place, intercepting MAP signals.

MRT emailed me an installation guide for a different FCD, which they said should work fine for this installation. I've posted it here:
http://docs.google.com/Doc?id=d532khn_11ddxw9gf9

The problem is, it's for installation in a WRX... which differs slightly. So I referenced my Haynes manual, and found that the MAP connector in the engine bay is a 3-pin connector in a sort of triangle shape.

Image

You can see someone had already tried to use these wires for something.... Pin #3 (bottom) is the signal wire, according to Haynes. I'm assuming this is where I'll intercept the signal from. That's not the issue.

My issue is that the installation guide says the FCD requires a 12v power source. The Haynes manual says the reference line for the MAP is 5v. So... is there a 12v line somewhere near the MAP that I can tap to power the FCD?

Lastly, if you notice anything wrong with my logic... let me know. I really wish the people who were doing electrical work on this car hadn't spliced in so close to the connectors.

Thanks.
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
n2x4
Fourth Gear
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Joined: Tue Oct 18, 2005 3:52 pm
Location: Massillon, Ohio

Post by n2x4 »

Any reason you're not sourcing the wires closer to the ECU? If you did it that way, you could find 12V no problem.

I kbelieve the Boost Control Solenoid runs 12V, you should be able to power it from there.
SUBARUEHS Racing
Fkyx
Third Gear
Posts: 842
Joined: Fri Nov 02, 2007 5:30 am
Location: Albany, OR

Post by Fkyx »

I've been mulling over mounting it closer to the ECU... it's so scary under the dash of my car though... not to mention very uncomfortable. lol

I'm going to scope it out a bit, and see what I can do about that, though. Time to look at some pinouts!
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
wtdash
Fifth Gear
Posts: 2349
Joined: Fri May 04, 2007 4:09 pm
Location: N. ID

Post by wtdash »

There's two 12v sources handy right where you are working - the BCS and the Pressure Exchange Solenoid ( the top of the 3 turbo sensors.)

Legacy SS FCD HEREfor reference on tapping them.


EDIT: I just noticed your Sig - EJ20 swap...so none of this may apply!

Td
Turbo Subies:
'87 GL-10 Turbo - SOLD
'90 BJ EJ22T/DOHC & 5speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX -SOLD
'96 BD-turbo'd-SOLD
'98 SF - NA-T
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