Codes 23, 49. EJ22T w/metal MAF. Choppy idle and misfires.

[hellosubaru]

I have an EJ22t with the metal MAF (Hitachi 22680 AA170). I'm getting codes 23 and 49 when I pull codes. I have swapped between two MAFs, cleared codes, and get the same results. Symptoms are choppy idle, misfires under load and cruise, and no power. Stalls almost constantly when throttle is applied.

The only thing I can think of is wiring. I have an EJ22e wiring harness. Is there any difference in MAF wiring between the NA and T MAF wiring? Any other ideas?

I've also checked resistances for the injectors, TPS, and coolant sensor (new sensor). All results were within spec (confirmed by no codes).

Let me know if I can provide more info. Thanks for the help.

-Jason

[hellosubaru]

Also, could someone list the functions of the red, white, black/red, black and blue wires on the MAF (like +5v, gnd, maybe iat?).

Thanks,
-Jason

Edit: I found this, which pretty much answers my question (gotta read those stickies!): http://www.surrealmirage.com/vrg3/ecupins/.

[hellosubaru]

Also, one more question. Is there any way to test the MAF sensor itself? All I can ever find is how to test the ECU terminals or the wiring itself.

[Legacy777]

There's not really a way to test the MAF.

Based on the fact you have both a code 23 & 49, I suspect your wiring because the chances of both of those coming up without the MAF being bad is pretty slim. There is likely a break in the wiring some where between the ECU & MAF connector. A simple resistance test with an multimeter will tell you that.

[hellosubaru]

Ok, thanks Josh. I will do the wiring/resistance tests today.

Is MAF cleaner safe to use on these MAFs? I know on some MAF sensors, it can do more harm than good.

[Legacy777]

Yeah, it should be fine to use, however I don't think that it'll make a difference.

Some people use brake cleaner, and that also is fine, as long as it's the stuff that doesn't leave a residue. Some contain petroleum distillates, which leaves a residue.

[hellosubaru]

I've done resistance tests, and all came back within spec. I'm going to measure voltages now and see what happens.

I also have two turbo ECUs with different part numbers: 22611-AA692 and 22611-AA694. Does it matter which I use? The parts catalog says the first one is 2wd/4wd, and the second is only 4wd.

-Jason

[wtdash]

I've done resistance tests, and all came back within spec. I'm going to measure voltages now and see what happens.

I also have two turbo ECUs with different part numbers: 22611-AA692 and 22611-AA694. Does it matter which I use? The parts catalog says the first one is 2wd/4wd, and the second is only 4wd.

-Jason

I'll give Josh a break....turbo ECU's are the same for '91-'94, manual and AT trans, from what I've read on here. There was no 2WD US turbo legacy.

GL,
Td

[wtdash]

Has the car ran properly since you've had it? If not, and this is a L-o-n-g shot, but see if the blue wire on the MAF, by some chance in he!!, is grounded. It allows the non-turbo/green label JECS/AUTECS MAF to be used...sort of (car will run Lean and then......pop.)

Td

[hellosubaru]

I just did all the voltage tests from the FSM, and they passed.

wtdash, I'll run down and see if the blue wire is grounded. Looking at the wire diagram, it should be +5V, correct?

I guess a little back story on the car would help now. In Sept, I put the car in the shop to do a full rebuild, and put a different turbo on the car (td05). Now the car will barely start, idles rough, stutters at cruise, and has no power.

Thanks for the help all.

Ninja Edit: Confirmed blue wire is +5V.

[wtdash]

I just did all the voltage tests from the FSM, and they passed.

wtdash, I'll run down and see if the blue wire is grounded. Looking at the wire diagram, it should be +5V, correct?

This is where Josh is your expert....but if your car ran fine b4 the rebuild (or @ least no MAF codes) and now doesn't, this isn't the issue.

RU testing the wiring from the MAF connector to the ECU? For continuity? Those MAF wires/connectors get brittle w/age and can crack/break....been there/seen that.

Td

[hellosubaru]

Yes, I did resistance testing from MAF connector to ECU connector, no problems found. To be honest, I can't remember if these codes were stored before the rebuild, they could very well have already been there.

You may be right, I may be chasing these codes, when they really aren't the problem.

-Jason

[wtdash]

Hold on a sec...re-read the initial post....you're using an EJ22e wiring harness on your EJ22T?

You state that you have an extra EJ22e harness? FWIW, the wiring for the MAF is the same....the ECU is what ID's turbo or NA MAF.

The car is a factory SS/TW and not an NA>>turbo swap, correct? You haven't ID'd the actual car yet, maybe that would assist? (not being a jerk...just double-checking)


EDIT: You just updated your SIG....that helps.

Also, you don't have a Revtronics ECU chip in either ECU, correct? It's designed to use the JECS/AUTECS MAF.

Td

[hellosubaru]

No problem, didn't take it as you being a jerk

I just made a signature with all my info in it. It was originally a 1986 GL, swapped to a EJ22e (with EJ22e ECU and EJ22e wiring).

I then swapped in an EJ22t, and swapped around the wiring for the cam/crank sensor, and added the boost sensor, pressure exchange solenoid, and wastegate controller (forgot the real name of this) wiring.

So, I'm using an EJ22e wiring harness, with an EJ22t ECU. I do not have an extra EJ wiring harness. Does than answer your questions?

Edit: No Revtronix chip in either ECU (at least, as far as I know, I've never cracked them open). I do have a home-made Revtronix cable though for datalogging. I've never used it though.

[wtdash]

Ok...cool project.

I'm stuck...sounds like you know what you're doing - I'm wiring phobic (yeah....even after doing my swap).

Td

[wtdash]

2 more questions:
1. What injectors? Stock EJ22T pinks?
2. What happens if you unplug the MAF? IIRC, it won't start/run @ all, but not 100%.

Lastly, clear the codes and see what comes back?
Td

[hellosubaru]

1. Stock EJ22T (pink) injectors, yes.
2. When I unplugged the MAF while it was running, the car died. Edit: the car barely runs, so I'm not sure if unplugging the MAF killed it, or if it just died on its own. I can't get it to hold idle very well anymore.

I've tried clearing codes several times, but the codes never go away. I'm following the directions here: http://www.surrealmirage.com/subaru/eng ... l#resetecu to reset the ECU (the "battery dance" method).

Thanks for your help, I totally appreciate it!

[hellosubaru]

Question about clearing codes: I'm doing the battery dance method for clearing the codes and resetting the ECU. After reconnecting the battery after an hour, the same codes are there right off the bat, the first time I turn the car to ON. I would expect the check engine light to flash steady after the reset, is that not the case?

[wtdash]

HI,
To clear the codes read up on using the GREEN connectors, which should be there from your EJ22 harness (same for turbo).

But maybe you can't even drive it enough to use the Green Reset?

Did you try the other ECU yet?

Td

[turboleg]

Purely a question, but can the ECU throw a MAF code from having a vac line disconnected or leaking? I've had EJ22 respond similarly to your description from this sort of thing. I don't recall ever seeing a code from it, but its been a long long time.

[hellosubaru]

wtdash, you're right, I can't drive the car long enough to use the green connector method. What is the other ECU reset method?

turboleg, I've checked for boost/vac leaks, but so far I've found none. I've sprayed carb cleaner around all the hoses, but haven't had the engine change speed yet. I'm going to give it another go this morning just in case I missed something.

[wtdash]

What is the other ECU reset method?

I don't know of any others...but you stated you had 2 turbo ECUs, correct? Do they both give you the same codes?

Td

[hellosubaru]

I don't know of any others...but you stated you had 2 turbo ECUs, correct? Do they both give you the same codes?

Td

Oh sorry, I misread your last post. Yes, I've tried the other ECU. When I plug in the other ECU, I get no check engine light at all, which didn't seem correct to me (with the black connectors connected).

[Legacy777]

Well what I'd suggest is taking a step back and looking at what specifically was done between when the car was working and now....which sounds like an ej22t swap.

What you could try is swapping the positive leads of the crank & cam sensors back to their original spots (assuming you just swapped the positive leads) and then try using the non-turbo ECU (Who is the manufacturer of your non-turbo ECU, hitachi or JECS?) The engine should run, and would at least tell you whether the wiring is ok, and/or if the turbo ECU might be bad.

If you get the same results, I'd rule out the turbo ECU. Then I'd go back and verify every single pin from the ECU to their termination sensor/point. This will give you all the pin info: http://www.surrealmirage.com/vrg3/ecupins/

You could really verify all the pins before swapping the crank & cam sensors.

What happens if you disconnect the MAF sensor before trying to start the engine?

[hellosubaru]

Well what I'd suggest is taking a step back and looking at what specifically was done between when the car was working and now....which sounds like an ej22t swap.

What you could try is swapping the positive leads of the crank & cam sensors back to their original spots (assuming you just swapped the positive leads) and then try using the non-turbo ECU (Who is the manufacturer of your non-turbo ECU, hitachi or JECS?) The engine should run, and would at least tell you whether the wiring is ok, and/or if the turbo ECU might be bad.

If you get the same results, I'd rule out the turbo ECU. Then I'd go back and verify every single pin from the ECU to their termination sensor/point. This will give you all the pin info: http://www.surrealmirage.com/vrg3/ecupins/

You could really verify all the pins before swapping the crank & cam sensors.

What happens if you disconnect the MAF sensor before trying to start the engine?

You are right about taking a step back. I think I got stuck on the codes, but I don't think they are the issue. Everything worked fine before the engine rebuild, so I think I need to do some more basic diag/troubleshooting.

I really don't think it's the ECU and wiring, because before I rebuilt the car, I ran the turbo ECU and repinned NA harness for a year with no issues. I followed your ECU pinout originally that you linked above, and it worked great!

I will try disconnecting the MAF sensor before trying to start and post results back shortly.

Thanks again!