MAF code 23

[whitewheels]

I finally bought myself a 94 turbo sedan. It have about 15000miles on it. No mods exept a turbo gauge.
I got it really cheap because it only ran 0,4bar boost (fail safe I thought). It turns out that they have hooked the wastegate accu diretly to turbo so it only gets wastgate press.....about 0,4 bar. So I plugg the BPV back in again and make a couple of runs with about 0,7bar of boost, then it´s starts to throwing cells......code 23 MAF. Rough idel,fuel cut,sound like running on 3 cyl sometimes,shakes and can barly get up to 60mph,and smelly exhaust. Then suddenly runns fine again but low boost(0,4bar). My friend with a 92 turbo est lend me his MAF(same color). Now a take aspinn around town and its getting boost properly and is running fine......the when crusin it´s just dies on me! Pull over and turn of ign and it´s start right up again. 3-4 miles more and it dies again,same proccedure and it goes on. Cold or hot engine doesen´t matter.
I´ve been checking the maf to ecu http://www.main.experiencetherave.com/s ... sting2.jpg and it checks out fine exept for the terminal to connector - (B1) no 2 to body/ 1M ohm min , I get 0 ohm. Does this wire go directly to the ecu or does it make a stop on its way? If not than I should be able to just bridge it direct to the ecu.

A couple of things that can be of intrest if someone wants to help.
I just got new sparkplugs(the old ones looked fine and even).
My friend thinks I´m imagen but I smell and feel like something is running hot under the hood. There was some oilleak that I cleaned up and the alt. is very very hot
Only gotten code 23

[whitewheels]

Sorry ,I meant 150 000 miles

And I have offcourse searched this forum but there seems to be so many different issues but no one thats spot on

[whitewheels]

......and the radiator fans goes on when the engine gets hot and stays on until I switch the ignition off

[whitewheels]

I´ll keep on speaking to my self

I change back to my old MAF.
After some full boost pulls last night I locate the burnt smell, It´s the 1st catalytic converter. So I was thinking that maybe it´s getting way to much fuel. So O2 sensor o temp sensor??
Donno if the engine fans are controlled via the tempsensor,but that can be one reason that they stay on all the time,but it should be running bad when the engine get up to op-temp. Sometime it does sometime it doesen´t.
Did some search here on trouble on o2 sensor. O2 sensor will defenetiv make the engine go rich but it´s very expensive. Is there a way to test it? I´ve heard that it´s hard to get it of the DP,any tip? Should it be warm or cold?

[whitewheels]

Anyone know if o2 sensor fit´s from other models and years?

I got a my94 legacy turbo EJ20

[mike-tracy]

Sorry that no-one has replied yet. You should have only 1 cat, it is in the DP, and 1 O2 sensor. Further down the exhaust is a resonator that sometimes is mistaken for a 2nd cat.

As far as the MAF sensor goes, do you have the aluminum body one, or plastic? Is there a way you can borrow a known good, reset your ecu and see if that helps? Also, try unplugging the o2 sensor and see if that changes how the car runs and if it gives off a new code.

[whitewheels]

ok.
I´ve tried another borrowed MAF from my friend turbo(still code 23 but differnt symtom)but when I return it I spoke to my freinds brother and he said that the they HAD have some troubles with thier to,so I´m not sure that I can exclude the MAF yet(I was told by my friend it would be ok). Now with the o2 sensor "thing" I have a feeling that it can be the problem.
I have the black plastic MAF with green lable.

Anyone who knows if I can use a o2 sensor of another subbie? Outback,newer Impreza, NA legacy etc.

[whitewheels]

A couple of days ago it died on me. Started to blacksmoke and backfire,stumble,very very low idle. I disconect the battery and after a couple of minuts it fire up but very bad idle,just bearly got it home. After that no start what so ever. pulled the plugs and they where soaked and black. Cleaned them and it fire up right away,idles bad with black smoke,after 5 min from nowhere the idle is rock steady again,another 5min and it goes bad again,until it just died. It started to smell burnt more and more and when the engn die the cat was glowing red hot!!!
Sooo.......any ideas?
Problem is that I really need the car running on tuseday morning,so I have time,right? I orderd a new bosch o2 sensor just in case,about to get a new water temp sensor tomorrow
Oh,and the thing wont start again. Probebly the plugs again.

I´ve search,but there actually not so common that the 02 senor o temp sensor is the problem. The big ? I´m going to check tonight is the timingbelt. Read alot of belts that jumped a tooth or two.

[whitewheels]

This thread maybe starting to be in the wrong section.......

Anyway. How about fuelpressure. If I have to much pressure will it affect the injectors?

[Legacy777]

Sorry that you haven't gotten many replies. I've been traveling and haven't gotten on the bbs.

I'm pretty confident your problem is related to the MAF sensor wiring.

I´ve been checking the maf to ecu and it checks out fine exept for the terminal to connector - (B1) no 2 to body/ 1M ohm min , I get 0 ohm. Does this wire go directly to the ecu or does it make a stop on its way? If not than I should be able to just bridge it direct to the ecu.

Based on your testing from above, and assuming the tests were good, it sounds like the wiring on that no 2 wire is shorting out on the chassis. It should go directly from that connector to the ECU. With the test you performed, you have continuity between the chassis and that wire....that should not happen.

You can try and follow the wiring loom and look for where there may be bare exposed wires, which I would suggest starting with. If you can't find anything, you could pull the loom off the wiring and snip that wire and connect a new wire to run to the ECU and connect right before the ECU. The only potential issue I could see is that the MAF wiring is shielded, so that wire wouldn't have shielding. It probably wouldn't affect things, but it's hard to say. It should run better than what it does now.

Take your time and try and follow the MAF wiring loom to look for the short where the wire may be touching the chassis.

[whitewheels]

Thanks Josh! That´s shall be looked at asap

This week I´ve checked my cat and it was not clogged. I drove almost 100km of boost and thought that was the key,but just as the odo turn 100km it started flashing check engine again That was yesterday and today,kidding you not ,the car stalled out like 50m from my house,in a junction Anyway that got me thinking that every time I pick up the kids from school it starts stumbeling and flashing check engine,sometime it goes away and sometime like today it get worse. I´m thinking heat soak! When I turn of the engine it sits for about 10min,since I started it cold at work 25km ago. I remember that this happends every time,more or less. I checked all the hoses,how about the coils? I remember reading that it was the heat from the plug "holes" in the camcovers that eventually make the coils crack and go bad. But all 4 plugs are soaked in petrol and sotty evenly! All 4 coil at the same time!? Maybe the ignitor? Any ideas what else are heat sensetive under bonnet?

[mike-tracy]

The coolant temperature sensor should be replaced with a new Subaru one before you get too deep into this, as the ECU makes a number of critical decisions based on information from that sensor. They go bad really slowly...

[Legacy777]

I can't discount the coils, igniter, or coolant temp sensor, but I really would suggest you address the MAF sensor wiring first. If you performed the tests correctly, you've already shown that you have a problem there. No sense in going any further until you address that problem, or retest to show that's not a problem any more.

[whitewheels]

I have my wifes car the coming week so hopefully I´ll have time to really get to the bottom of this.
Anyway,I have a new oem tempsensor and a new Bosch o2 sensor,but first I´ll get this maf wiring sorted.

What does it mean that the wire is sheilded?? I was thinking cutting in with a T every 30-40cm of the wireing until I get the proper ohm readout. Will I damage the sheild in the oem wire if I´ll do so?

[wtdash]

Wire Shielding:


I wouldn't worry about it for your MAF testing. Just run the replacement wire as noted by Mr. JC.

GL,
Td

[whitewheels]

Got a real multimeter, and all the messures checked out for the MAF.
Change the temp sensor in frustration but the old one was ok so I knew it wouldn´t help.

I always get the 23 code. Easy right? just get a new MAF. Yes if they weren´t so expensive I would. So I went back and borrowed my friends MAF again. I still get tha 23 code but a diffrent problem,and most important,I don´t get the same problem of soaked plugs and black smoke,poor poor ideling. With the borrowed MAF the engine stalls out now and then. Fires right up tough. It get poor ideling but not inte the same way.
So if I would have any other problem but the MAF it should reaccour right? No matter what MAF I´m running.

If I would get my self a new MAF,where do I get the cheapest one? Not used.
There is a couple of used here in sweden but they still to expensive to take a chanse. I mean,what to say that they aren´t aswell .
On monday the car have to run. Is there some hazard of running it in fail safe/limp home mode?

[Legacy777]

Was the part # on the MAF sensor you borrowed from a friend the same as what's in your car?

Another option you can try is running your MAF sensor in his car to see if it works. If it doesn't work, or you have problems, then there's a good chance the problem is the MAF. If your friend's car works fine, then your problem isn't likely the MAF sensor.

Have you tried the active diagnostic with only the green connectors plugged in?

[whitewheels]

My friend leggy is in pieces,otherwise it was a great ide.
Yes I have performed the d-check.......noting

Is there other MAFs that at interchangeble with mine?

[wtdash]

Is there other MAFs that at interchangeble with mine?

What is yours? The green label? If so, in the US, any Impreze/Forester/Legacy from '92-98 will work from a non-turbo car.



If yours is the orange/yellow/purple label, I don't know.


EDIT: In the US, the turbo models and the '90-'91 NA models have a silver Hitachi - version...



Td

[mike-tracy]

^^ He has a turbo. Which year(s) NA had the aluminum MAF then?

[wtdash]

I don't know if they are US or not..since his is an EJ20 and they use BAR vs. PSi, I'm guessing he's not 'local'....re-read and found this:
"I have the black plastic MAF with green lable".

So either running the incorect MAF for an EJ22T ECU or running an EJ20G ECU and CAN USE the NA MAFs.

Where are you?

Td

[mike-tracy]

Derp - he even said he has the plastic MAF in reply to my previous question. Good catch again, Todd. Using miles, but measuring boost in BAR I'd say the UK, right?

[northcoast]

Is there other MAFs that at interchangeble with mine?

What is yours? The green label? If so, in the US, any Impreze/Forester/Legacy from '92-98 will work from a non-turbo car.



If yours is the orange/yellow/purple label, I don't know.


In the US, the turbo models have a silver Hitachi - version...I don't know of any interchange.


Td

I'm confused... my NA wagon has the silver version stock. I've tried the black one and my car runs like poo with that one.

[mike-tracy]

As I alluded, USDM N/a's got the same silver MAF as the turbos - for a year or two. You need to run the MAF your ECU is tuned for. I have a couple spares.

[northcoast]

The silver ones are hard to find.

and based on my MPG I don't think my ECU is tuned at all! but that's another thread. Back to this one!