Select Monitor Data and Lambda trouble

[trac]

I've asked a guy i know who prepares harnesses for people who want to install a legacy engine in there vw or trike and he has confirmed me that the two wires from the temp. sensor go to the ecu and one wire from the thermistor goes to the temp gauge.
Anyway, nothing that could be a wiring issue infuencing my ecu and lambda/Alpha values.

[Legacy777]

Were you able to use the select monitor on a friend's legacy to see how its values compared?

[trac]

Were you able to use the select monitor on a friend's legacy to see how its values compared?

No, I haven't tested my select monitor on someone else his Legacy.
A friend did test his select monitor on his Legacy I 2.2 and on that car the lambda values were going up and and down and Alpha and Load Data values responding to revving the engine.
So basicly everything that should happen looking at those sensors in the Select Monitor.

I have to see what my next step is going to be.
Hook it up to a exhaust analyzer maybe to verify it's mixture. I don't know, so strange why my lambda won't cycle as it should.
Also can bring the car to an Subaru expert, but so far can't see what they can find what I haven't measured or tested.
I can replace a whole bunch of sensor to 'see what happens', but I'd like to have some clue what I'm doing.
Would you know of any sensor that can have any influence on readings like the lambda?

Bram

[Legacy777]

Would you know of any sensor that can have any influence on readings like the lambda?

Bram

The coolant temp sensor. Honestly, at this point, I'd really suggest just replacing the sensor. I know all the values show ok, but other than replacing the ECU, I'm out of ideas. In the US, the coolant temp sensor is around $20 USD. So it's not too expensive and as discussed can affect a lot of things with the ECU because it bases things like all the fuel enrichments, warm up, start up, acceleration, etc on the coolant temp sensor.

I think getting a wide band O2 sensor or having a shop with one measure the air fuel ratio would be a good next step. I would recommend taking the reading before any catalytic converters. I've been told they shouldn't alter the reading, but I don't necessarily believe that.

[trac]

Thanks again Josh for all your help.
I'll continue to do a number of tests here and if I find something I'll of course post it here.

Thanks so far, Bram

[Legacy777]

You're welcome.

Let us know what you end up finding out.

[trac]

Quick update, did some testing with the exhaust analyzer today.

O2 sensor connected:
3000rpm: 2,5 % CO , 160 ppm HC
Idle: 2,6 % CO, 190 ppm HC

O2 sensor disconneted:
3000rpm: 2,6 % CO, 95 ppm HC
Idle: 2,7 % CO, 150 ppm HC

Coolant temp. 85C

Two conclusions:
- O2 sensor connected or not doesn't make a difference.
- Mixture is rich

Please note, there is no catalyst converter installed in the exhaust. Completely open downpipe and exhaust, only a small muffler at the rear.

I was wondering; with my O2 sensor not giving any values, could it be that because of the rich mixture, it's out of it's range measuring the mixture?
Since there're mulitple O2 sensors tried so far, and all giving no or strange values, I kind of excluded the O2 sensor being faulty.

One thing I did observe. When the car was kind of warming up (coolant aroud 40C) and I already had the analyzer connected, the CO was at 1,1% CO and climbing. Up to the point when completely warmed up when it was showing 2,6% CO. Wouldn't surpise me that the climbing of the CO goes together with the strange dropping of the lamdba value in the Select Monitor to 0,0V.

Gr. Bram

[Legacy777]

Just out of curiosity, have you tried verifying/testing the O2 sensor wiring from the ECU to the sensor connector plug? You can use a multi meter and check the resistance to make sure the wiring is good. You should have 0 ohms or close to it.

[trac]

Sorry Josh for not getting to that point, car developed other problems later on.
Been away a lot and also busy on my other Mercedes projects which went perfectly btw, but this Subaru project keeps buggng me...
Latest update over here:
http://bbs.legacycentral.org/viewtopic.php?f=19&t=49855

As soon I have the car back at home, it's time to go a new round replacing parts and testing a whole lot...will get there...

[Legacy777]

No worries.

I replied to your thread....sounds like you have a dead cylinder.