Jecs Maf

The big weave · Post by **The big weave** » Wed Sep 02, 2009 6:06 am

Got a jecs maf off a 93 1.8 impreza and was wondering if I could use it. Put it on and the car had no power and would spudder out and I got a nasty ping at idle.

BSOD2600 · Post by **BSOD2600** » Wed Sep 02, 2009 11:29 am

Unless you do the wire ground hack (search, several threads documenting what wire needs to be modified to make the ECU happy) or have after market engine management (Revtronix, pp6, etc), you cannot use the JECS.

The big weave · Post by **The big weave** » Wed Sep 02, 2009 10:29 pm

I have the rewire done, or is there more than just running new grounds to the battery?

mexicanzero · Post by **mexicanzero** » Thu Sep 03, 2009 1:39 am

the blue wire in the harness going to the maf has to be grounded, if you look at the plug in on the mafs you'll notice the stocker has a pin where the blue wire goes in the jecs doesnt.
just ground the blue wire.

-Alex

race_to_live · Post by **race_to_live** » Thu Sep 03, 2009 4:46 am

ok so im doing the td04, wrx tmic, revtronix stage 2 deal and i need this so called JECS MAF. how do i go about getting one of them? is it just a newer car thing? can i just go to the junk yard and pick one up? is there one that you just "bolt on?"

(sorry for all the questions)

ericem · Post by **ericem** » Thu Sep 03, 2009 4:50 am

Get it from a N/A automatic legacy. For sure the 93 Legacy works. Any N/A legacy or impreza or outback from what I understand has this MAF sensor.

race_to_live · Post by **race_to_live** » Thu Sep 03, 2009 4:51 am

so just plug in and go?

ScottyS · Post by **ScottyS** » Thu Sep 03, 2009 5:39 am

Yes. Most mid-90's N/A Subies should have it.

The big weave · Post by **The big weave** » Thu Sep 03, 2009 6:18 am

Why is it that you have to ground that wire and if i do the chip do I have unground if I get the revtronix chip?

BSOD2600 · Post by **BSOD2600** » Thu Sep 03, 2009 10:01 am

The revtronix chip compensates for the different wires present in the JECS vs AUTEC MAF's. Prevents the CEL from turning on because the MAF is different from what the ECU is expecting. The MAFs are also calibrated differently. So while you can make the JECS "work" on the stock ECU with the wire mod, it will be sending different/wrong data back to the ECU.

mexicanzero · Post by **mexicanzero** » Thu Sep 03, 2009 11:31 am

yeah dont use the jecs maf without the chip or some sort of em cuzz for the same amount of air going in it will tell the ecu a lower voltage than the stock maf so you'll go lean without em.
if you use the chip the blue wire doesn't have to be grounded

-Alex

The big weave · Post by **The big weave** » Fri Sep 04, 2009 7:20 am

Yeah, tired the grounding mod and it did not help the way the car ran at all, just gunna order the chip.

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Jecs Maf

Jecs Maf