Advice from those with Subaru service manuals.

boostjunkie · Post by **boostjunkie** » Fri Dec 12, 2003 4:29 pm

I've got code 41 coming up intermittently, which is for the a/f learning control. My a/f displays some crazy readings, mostly staying in lean, sometimes rich.

However, what I noticed was that when the car is cold (ie: open loop mode), the car would run a little more normal.

First things first. What does the Subaru service manual say to check for code 41? And, is there any way for me to have the ecu run open loop all the time? I know this will reduce my mpg, but at least it will be a little safer than the way I'm running it now.

vrg3 · Post by **vrg3** » Fri Dec 12, 2003 4:53 pm

If I remember right the service manual says to diagnose a code 41 you just check pretty much everything: MAF sensor, oxygen sensor, TPS, water temperature sensor, injectors, fuel pressure regulator...

You should be able to make your car run open-loop by disconnecting the oxygen sensor from the ECU. I believe that will also make it use the base ignition map.

I think disconnecting the knock sensor also makes the ECU run open-loop with the base ignition map, but this may be more dangerous.

boostjunkie · Post by **boostjunkie** » Fri Dec 12, 2003 5:04 pm

vrg3, you're full of great news.

So, what does the manual say for diagnostic tests for all of these sensors? I already checked the TPS and MAP sensor, from the previous error codes. That leaves:

Crank, cam, knock, MAF, o2... anything else?

Could it also just be my ecu takin a dump? Are you going to be in the area again for this coming holiday season? I was thinkin of checkin the ecu by plugging in your extra ecu.

Also, would there be any detrimental effects (stalling, etc) other than fouling of plugs and o2 sensor from running in open loop mode?

Post by **Legacy777** » Fri Dec 12, 2003 5:15 pm

You can look at a manual yourself.

people should really look at my posts

http://bbs.legacycentral.org/viewtopic.php?t=14485

http://www.main.experiencetherave.com:8 ... lectrical)

You can check sensors.....but it wouldn't surprise me if your ECU is on a downward spiral.

boostjunkie · Post by **boostjunkie** » Fri Dec 12, 2003 6:15 pm

Now that is one big@ss file!! My crappy work computer is STILL trying to open it!!

Another thing about my crazy a/f readings. When I'm coming to a stop and put the shifter into neutral and apply the brakes relatively hard, sometimes (not all the time), I can make the a/f readings change from off the gauge (really, really lean) to around stoich. *shrug*

Brat4by4 · Post by **Brat4by4** » Fri Dec 12, 2003 6:45 pm

Car is injecting more guess to keep the idle up. My gauge has never read stoich. It's either rich when there is enough gas, bouncing when cruising or idling, and lean or off the meter when coasting.

Well, one time it DID read stoich and sometimes lean under full boost

. But there was something going on with the gauge (or sensor) and not the car.

ciper · Post by **ciper** » Fri Dec 12, 2003 7:43 pm

I think you should rule the A/F gauge out. Disconnect it and return the vehicle to normal then reset the ECU. Try what you are saying. Who knows if the Gauge is malfunctioning and putting voltage into the curcuit!

boostjunkie · Post by **boostjunkie** » Fri Dec 12, 2003 7:44 pm

My gauge used to read out the way your's did. Bouncing back and forth between rich and lean while in closed loop mode and then full rich in open loop. Now, it gets really crazy. And sometimes is fine when the engine's still cold.

Even the code will come on randomly from time to time. I just reset the ecu and went for a 30 min drive. No code!! Same symptoms, tho.

I'll check the gauge again, but I still doubt that's the culprit.

ciper · Post by **ciper** » Fri Dec 12, 2003 8:08 pm

Why not, the issue is with a a/f code and you have something plugged into the a/f meter that normally isnt. Electronics can fail, not knowing how you have it connected it seems that it would be pretty easy to temporarily remove.

After resetting the ECU is there a certain time the CEL is shown? Can you recreate it?

You could connect a volt meter instead of the gauge if you wanted to be sure the A/F was still acting up.

boostjunkie · Post by **boostjunkie** » Fri Dec 12, 2003 9:27 pm

The occurence of the CE light is completely random. Sometimes it shows up and sometimes it doesn't. It will turn off about 5-10min after it is displayed, however.

vrg3 · Post by **vrg3** » Fri Dec 12, 2003 11:03 pm

I am probably going to be in the DC area for a few days between Christmas and New Year's. We can do some experimentation on your car then.

boostjunkie · Post by **boostjunkie** » Fri Dec 12, 2003 11:17 pm

Sounds good to me.

Post by **Legacy777** » Sat Dec 13, 2003 3:47 am

boostjunkie are you right clicking and saving, or are you just clicking on the link and opening it?

boostjunkie · Post by **boostjunkie** » Sun Dec 14, 2003 1:59 am

I actually saved it to my hardrive and tried opening it. It still takes forever.

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Advice from those with Subaru service manuals.

Advice from those with Subaru service manuals.