Maf Question

[snowjob]

Ok so just when I figure i've got all the bugs out of my ej20 conversion, I get a maf code on my ecu, so it could be two things, a bad maf(it was working on my old car) or incorrect wiring.
Does anyone have the MAF pinout at the maf, wher it sais abcde
I know a is power, but the others???
Any help or suggestions would be great.

[vrg3]

If you unplug the MAF sensor's harness connector and look at it head-on with the locking tab on top, the pins are numbered 1 through 5 left-to-right:

Code: Select all

 ----| |----
| 1 2 3 4 5 |
|___________|

These are the pin specifications:

Pin 1: Red wire, power supply (+12v)
Pin 2: White wire, signal ground
Pin 3: Black-with-red-stripe wire, ECU ground
Pin 4: Black wire, signal
Pin 5: Blue wire, sensor ID (grounded by Hitachi sensor, not used by JECS sensor)

Which MAF code do you get? Which sensor and which ECU are you using?

[snowjob]

I get 4 long lights and 9 short lights.
It's a hitachi sensor and I've tried both my ecus and get the same error for each.

[vrg3]

Which ECUs are you trying?

[snowjob]

jdm k9
EDM G7

The two ecu's in a thread below that I was trying to identify.

[vrg3]

Oh.

You need a JECS MAF sensor. I believe the one from your 92 that you're parting out will do.

[snowjob]

oh

want to sell me yours vr3? How much?

[snowjob]

Posted: Sun Feb 27, 2005 7:07 pm Post subject:

--------------------------------------------------------------------------------

No.

All turbos and all 90-91 5MTs use the Hitachi MAF sensor.
All 90-91 4EAT non-turbos and all 92-94 non-turbos use the JECS MAF sensor.
_________________
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212

I"m confused VR3 I just read this post you wrote, by this reasoning I should be using the hitatchi right??

[vrg3]

Hm? I don't have a spare JECS sensor. I'm sure someone else on the board can help you though. The JECS sensor that I think you need, part number 22680AA160, was used on most Legacies and Imprezas up through 1998 or so, including all 92-94 non-turbos.

[snowjob]

why Jecs, My engine is a Turbo?

[vrg3]

Oops, didn't see the new post.

You need to use the correct sensor for your ECU. The stock EJ22T ECU is a Hitachi unit, so it uses the Hitachi MAF sensor.

But you're using these JECS ECUs, so you need the sensor that goes with them.

[snowjob]

ahh o wise one, I see the light.

[skid542]

Bringing up an old thread here, but, I have a direct question on Vikash's pinout and using it for my MAF Pro.

I understand that pin 4 is the signal wire and the wire that I will feed the signal out of my controller. My question is, do I need to ground pin 2 or does the ECU do this? I assume the ECU does it on it's own and I don't need to worry about it.

But I thought I'd ask just incase. Many thanks.

[Legacy777]

Lee,

Not sure I understand the question. How is the MAF Pro hooked up? You should just be intercepting signal wire only. Pin 2, the ground signal ground is an ECU reference ground, and should NOT be combined to a chassis ground.

[skid542]

Josh,

10-4 on not hooking the signal ground to the chassis ground.

The MAFT Pro allows me to run a MAP system and get rid of the MAF. It does this by installing an IAT and a quality MAP sensor. The system takes these values along with a couple other inputs and outputs a fake MAF signal to the ECU to control the fueling. This is what allows the system to handle larger volumes of air and bigger injectors.