legacycentral bbs

Long time no talk, fellas.

I moved for school a couple weeks ago, and the city I moved to requires emissions testing. I installed a couple cats and thought I'd be laughing, with my 91 Legacy motor in my 83 Brat. Nope.

They only did the idle test, but HC was 665 and CO was 6.83%, both about 50% above max allowed.

From what I've read on the forums, thats also about 10x higher than most legacys seem to get.

I've got a fairly limited amount of diagnostic equipment with me here, I've got an automotive multimeter which can measure duty cycle, dwell and pulse width, then just your standard hand tools.

Given how far out to lunch those numbers are, it must be something pretty significantly wrong. Could an incorrectly routed PCV system cause such a huge error? The only codes I have are for a cam angle sensor and VSS. The cam angle sensor I don't know why I have it because I tried 2 other sensors and it didn't fix it. The VSS just isn't wired up with the swap, but I don't see how that could cause anything this far off base...

Yeah, long time no see! Good to hear from you.

High HC's is fuel, so you're running rich. My suggestion would be to replace the coolant temp sensor if it's got some miles on it. However, I'd also suggest focusing on the codes. Have you tried clearing the codes with both the green & black connectors, if so did they clear? Also, if you do just the green connectors (active diagnostic) what codes show up?

Have you checked the resistance of the cam sensor wire from the sensor to the ECU? If you have the older style cam sensor, you'll have to pierce the insulation to get a reading. The newer style sensor has a connector you can just unplug. If the car runs ok otherwise, I would suspect this is a bogus code.

Regarding the VSS, you need to hook that up. These ECU's have quite a bit of speed dependent variables tied into them as well as fail-safe tuning, and that very well may be why you're running rich.

That's where I'd start, and most of that should be able to be accomplished with the tools you have.

I had a problem with a bad injector and then the wrong ecu when I was trying to get my Brat to pass emissions.

Did you have a donor car when doing the swap or did you piece it together like I did with mine?

I had to piece it together, the computer did come out of another legacy but it came out of the same year and transmission.

The car failed the Idle test, I'll see about hooking up the VSS but I don't see how that can come into play when the car isn't even moving.

Coolant temp sensor is definitely something I'll check, and of course check all my wiring has continuity from the terminus to the ECU.

The codes will NOT clear, even with disconnecting the battery for days. I wonder if it could be a defective ECU...

I have one car the battery dance method doesn't work I always have to do outher method to clear codes.

Oh FFS, I have the wrong damn MAF I just realised. At least I think so.

The ECU is from a 91 NA 5MT, and I have the black JECS maf.

I need the metal MAF, don't I?

Yup! Forgot to mention I had that problem with one of my ECU's I was running it through a code for the wrong MAF.

Sorry about that.

A friend has a spare auto ECU, gonna try that out tonight. Fingers crossed.

Dang his JECS ecu was fried, didn't even prime the fuel pump.

I did confirm that my ECU is a hitachi tho, so should any hitachi maf work, even from a turbo?

EDIT: Just looked through the parts catalog, yea looks like I need a metal hitachi maf from a turbo. I'm pretty sure I have one at my parents place, see if I can get them to find it and mail it to me

So you must not have hooked up the additional wiring that would tell the ECU it has the wrong MAF....because otherwise you would have a code for the wrong MAF.

I guess let us know if swapping the MAF fixes things.

Yowza... got the hitachi maf on tonight and I think my gas mileage is about go through the roof. This thing has a ridiculous amount of power now, it's hard to keep my foot off the throttle

Taking it back for a retest monday, I'll update with the results!

Glad to hear it's running better!

haha soooo....

HC dropped from 665 to 47 (max allowed 408)
CO dropped from 6.83 to 0 (????, max allowed 4.60)

Car has officially passed emissions.

Fun fact: Even if this engine was still in a 91 Legacy, it would have breezed through the test.

Yup......these engines run surprising clean when everything is running properly. Even without a catalytic converter they are pretty clean, but with a catalytic converter they are very clean.

Is this EJ22E turbo swapped? And it's super awesome you swapped a brat I really want one so I'm pretty jealous

With a cat I'm pretty sure running around 0 CO is the norm. It should all be harmless CO2.