Mass Air flow sensor problem

[96gsxwi]

i Just bought a 95 eclipse gst 5 speed and the check engine lights on and it said the #4 wire on the mass air flow sensor is faulty so my question is were does that #4 wire go to so i can replace it THANK YOU

i have bought a haynes manual and it does not have wiring schematics for it

 

[BLINKY619]

google...

 

[iron bird]

does obd 2 really point out witch wire

 

[luv2rallye]

#4 red wire is the +12V power wire from the MPI relay.

 

[96gsxwi]

ok i have gotten mpi out how do i test it? and how should i go about checking wires? please sorry if this is a stupid post i just really need help

looking at the mpi wiring theres power between the blue and red wire so thats the fuel pump side? and between the black /white and black/ red theres no power??? that the mpi side that im having problems with?

 

[luv2rallye]

Well if the problem is the MFI relay it is tested thus: http://www.dsmtuners.com/forums/att...3d1197004327-mfi-fuel-pump-relay-2-small-.jpg

If there is +12v to all other solenoids/sensors but not the MAF, you can just run a red wire from one of those to MAF #4. Other solenoids/sensors on red wire: http://www.dsmtuners.com/forums/new...-engine-fuse-keeps-blowing.html#post151181220 Disconnect battery negative while connecting new wire.

 

[luv2rallye]

Ok I didn't realize you had a 95. I was just looking at the car year under your post name (96) but now I just reread your first post, sorry. The 95 is different than 96-99 as the MPI and FP relays are in the same relay box. How many pins are on your relay and is it MR161519 or MR224160?

Assuming you have the 8 pin one (not 10 pin), power for FP is the black-white on pin 7 (its coil is also this pin). Power for MPI is the red-black on pin 4 (and for its coil on pin 8).

To test FP half, put +12v on pin 7. Then when ground (battery negative) is applyed to pin 5, +12v should appear on pin 1.

To test MPI half, put +12v on pins 4 & 8. Then when ground is applyed to pin 6, +12v should appear on pins 2 & 3.

 

[96gsxwi]

<a href="http://s653.photobucket.com/albums/uu257/jhell4445/?action=view&current=0630002317.jpg" target="_blank"><img src="http://i653.photobucket.com/albums/uu257/jhell4445/0630002317.jpg" border="0" alt="Photobucket"></a>

the car starts and runs fine

ok sorry about the 95/96 confusion i have a 96 gsx but i just bought a 95 gst and looking at the pic i posted can u tell me what pins are what color to test for mpi its either relay or wire from there to maf but the red wire going to maf gets power?

 

[luv2rallye]

95 MPI/FP relay (8 pin):
Is yours an 8 pin?

I don't have a pic of the pins layout so you'll have to figure it out from the following pins/wire colors:
pin 1: black-blue (ie. black with blue stripe or marking. black is the predominent color)
pin 2: red
pin 3: black-red
pin 4: red-black
pin 5: white-red
pin 6: blue-green
pin 7: black-white
pin 8: red-black

Use either pin 2 or 3 for MPI relay output to drive the MAF pin 4. It looks like the original wiring uses MPI pin 3.

 

[96gsxwi]

so just cut the wire of # 3 pin and run straight to red wire on maf?

 

[steve]

i have bought a haynes manual and it does not have wiring schematics for it

http://www.dsmtuners.com/forums/fre...stions/324090-download-2g-service-manual.html

There are differences on the 95's from these but it will still help.

 

[luv2rallye]

so just cut the wire of # 3 pin and run straight to red wire on maf?

Don't cut the #3 pin wire since it goes to other things also. Just splice into it (or cut it but then connect all 3 ends together). Then splice your new wire into the red wire (pin 4) on the MAF. Solder all connections.

 

[96gsxwi]

so cut wires at pin 2 & 3 and connect all of them together?

so cut wires at pin 2 & 3 and connect all of them together? and then run the new wire straight to the maf pin 4 (red)

 

[luv2rallye]

Either splice your new wire into MPI #3 wire without cutting it OR cut MPI #3 wire and connect the ends of the wire you just cut together with your new wire (thus 3 wire ends). To be safe disconnect battery negative first.

 

[96gsxwi]

ok thank you ill post in morning how it went

 

[96gsxwi]

ok i did what u said and spliced red maf wire #4 into the # 3 on mpi and still nothing...

i also tried the # 2 wire and still nothing... im about to give up ... could u help me test the wires on the maf sensor? i get code p0100 with scanner mines just a cheap one tho. what should the wire each read? can u please help me

 

[whoa]

What was the car doing when you got that malfunction code? Did it start up and run? Idle bad and bog down when you give it gas? P0100 is VAF circuit malfunction. I'd suggest that the first thing you should do before cutting wires and shit is try another MAF, and if that doesn't work pull the ECU out and open it up. Look for burnt components, mainly a burnt ground track as seen here http://www.dsmlink.com/wiki/blownsensorground?s=sensor ground

If this is the case, it's a simple matter of soldering in a strand of copper wire where the ground track burned.

 

[96gsxwi]

ok new problem.... that wire going into maf was getting 12+ volts the whole time... ok whats going on is im getting code p0100 my plugs keep on fouling out within a few min they are full of black soot too much fuel right? i just wanna start from the beginning

the car idles ok it breaks up at 3k for the first like min of idle then after that it dont it just runs fine unless ## driving it and wot get to about 5k then it breaks up? i honestly dont know were to begin now

 

[whoa]

ok new problem.... that wire going into maf was getting 12+ volts the whole time... ok whats going on is im getting code p0100 my plugs keep on fouling out within a few min they are full of black soot too much fuel right? i just wanna start from the beginning

Ok, so start from the beginning. First thing you should try is replacing the MAF. Either go find one at a junkyard, ask a buddy to borrow a known good MAF, whatever. This should be the first step for sure.

If you're still having a problem, move on to other things, replace MFI relay, check ECU like I posted above.

 

[96gsxwi]

ok i have 2 other mafs and tryd them and mfi relay is good i tested that and i just took out ecu and it looked good

 

[whoa]

Look closely at the ECU, it's hard to see where the ground track burns. If it is burned, you will see the burnt track where the bare copper wire strand is soldered in, directly above the mounting screw in this picture.

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[Sam@RRE]

does the car have an AFC or if anyone has installed an AFC on it. Quite possible that it went jenky.

 

[steve]

Blown sensor ground was my first thought but you usually get other errors and may not be able to start the car at all.

 

[whoa]

Blown sensor ground was my first thought but you usually get other errors and may not be able to start the car at all.

I just spent a week trying to figure out what was wrong with a 95 talon that was given to me. I had 2 ecu's, and since I had 2 I assumed that there was no way both could be bad. The car would start up but idled terribly and wouldn't reach higher than 2000rpms. Come to find out both ECUs had blown sensor grounds

I guess the guy who had it before me had an accident with an O2 sensor. Hit a bump and busted the end of it off. Shorted out and burned the ECU. He bought another ECU and that one was burned by the same short, haha.

 

[96gsxwi]

im getting a a code 4 o2 sensor also i took out ecu and looked very carefully and there was nothing.... but also the guy i got the car from had a turbo timer and other things but they were stolen and i found a harness comming off the ecu with 10 wires going to a plastic connector... is that for safc? if the safc is remover ans harness is still plugged in would that make it do that?

i have codes p0100 and p0143 and some evap purge valve c code

http://i962.photobucket.com/albums/ae110/fatihlenee/DSC00774.jpg

http://i962.photobucket.com/albums/ae110/fatihlenee/DSC00775.jpg

http://i962.photobucket.com/albums/ae110/fatihlenee/DSC00776.jpg

http://i962.photobucket.com/albums/ae110/fatihlenee/DSC00777.jpg

first 2 pictures are of harness i found comming off ecu 2nd pic is close up of plud of harness and 3rd pic is thermostat housing notice bottom center of pic theres a plug missing were does that harness come from and the last picture is on the firewall behing the t/b some wires i found are them suppose to be connected?

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this is pic of my ecu also is it eprom?