2000 Legacy stalls when clutch is depressed

[2000 Legacy]

You're right, thats exactly what happened. I had the air filter housing off and unplugged the air intake sensor but didn't run the car. Thanks again. I'll be in touch once I get the Innova 3130.

[2000 Legacy]

Hi OB99W, Fairtax4me, DaveT and everyone else who has helped me with this problem,

 

I really do appreciate everyones efforts and for not quitting on my problem. I'm so excited, I just recieved my Innova Equus 3130 and these are the results:

 

Before starting the car I plugged in the 3130 and it read as follows:

1/7 codes, "G" in the upper right corner, "EVA" blinking, Freeze Frame is highlighted.

 

!st code: PO304,

Freeze Frame Data:

- Fuel Sys 1: "CL"

- Calc Load %: "7.8"

- ECT (F): "132"

- STFT B1 (%): "-14.8"

- LTFT B1 (%): "-1.5"

- MAP (inHg): "18.8"

- Eng RPM: "772"

- Veh Speed (MPH): "0"

2nd code: PO302

3rd code: PO303

4th code: PO301

5th code: PO113

6th code: PO302 with "Pending" blinking

7th code: PO304 with "Pending" blinking

 

After I read and documented the above, I started the car and pressed the "LD", Live Data button and took the car around the block, 1 mile and got the following results:

 

Live Data:

- Fuel Sys 1: "OL"

- Calc Load %: "0"

- ECT (F): "170", however it did drop after as I was documenting.

- STFT B1 (%): "0"

- LTFT B1 (%): "-10.9"

- MAP (inHg): "29.2"

- Eng RPM: "0"

- Veh Speed (MPH): "0"

- Spark Adv: "10"

- IAT (F): "68 degrees"

- MAF (1 lb/min): "0"

- TPS (%): "0.3"

- O2S B1 S2 (V): "0.920"

- STFT B1 S2 (%): "0"

- OBD Sup OBD2

- O2SB1 S (V): "3.796"

- EQ Ratio 11: "0.999"

 

Now I'm not sure that I did things correctly since the 3130 is new to me and I'm unfamiliar with it. I've tried to read the manual to understand it better, however I'm ashamed to say I hate to read manuals, they seem confusing.

 

I hope that the above results help to solve the mystery, please let me know what your thoughts and suggestions are. I was wondering if I should clear the codes and start fresh (no codes) or if I should have driven the car further/longer distance but I thought I had read that Live Data was best captured when the problem is more prevalent. I think that it's important to note that the car stalled around the block every time I pushed in the clutch to either stop or downshift.

 

 

Thanks.

2000 Legacy

[2000 Legacy]

Hi OB99W, Fairtax4me, DaveT and everyone else who has helped me with this problem,

 

I really do appreciate everyones efforts and for not quitting on my problem. I'm so excited, I just recieved my Innova Equus 3130 and these are the results:

 

Before starting the car I plugged in the 3130 and it read as follows:

1/7 codes, "G" in the upper right corner, "EVA" blinking, Freeze Frame is highlighted.

 

!st code: PO304,

Freeze Frame Data:

- Fuel Sys 1: "CL"

- Calc Load %: "7.8"

- ECT (F): "132"

- STFT B1 (%): "-14.8"

- LTFT B1 (%): "-1.5"

- MAP (inHg): "18.8"

- Eng RPM: "772"

- Veh Speed (MPH): "0"

2nd code: PO302

3rd code: PO303

4th code: PO301

5th code: PO113

6th code: PO302 with "Pending" blinking

7th code: PO304 with "Pending" blinking

 

After I read and documented the above, I started the car and pressed the "LD", Live Data button and took the car around the block, 1 mile and got the following results:

 

Live Data:

- Fuel Sys 1: "OL"

- Calc Load %: "0"

- ECT (F): "170", however it did drop after as I was documenting.

- STFT B1 (%): "0"

- LTFT B1 (%): "-10.9"

- MAP (inHg): "29.2"

- Eng RPM: "0"

- Veh Speed (MPH): "0"

- Spark Adv: "10"

- IAT (F): "68 degrees"

- MAF (1 lb/min): "0"

- TPS (%): "0.3"

- O2S B1 S2 (V): "0.920"

- STFT B1 S2 (%): "0"

- OBD Sup OBD2

- O2SB1 S (V): "3.796"

- EQ Ratio 11: "0.999"

 

Now I'm not sure that I did things correctly since the 3130 is new to me and I'm unfamiliar with it. I've tried to read the manual to understand it better, however I'm ashamed to say I hate to read manuals, they seem confusing.

 

I hope that the above results help to solve the mystery, please let me know what your thoughts and suggestions are. I was wondering if I should clear the codes and start fresh (no codes) or if I should have driven the car further/longer distance but I thought I had read that Live Data was best captured when the problem is more prevalent. I think that it's important to note that the car stalled around the block every time I pushed in the clutch to either stop or downshift.

 

 

Thanks.

2000 Legacy

[OB99W]

I don't have the time right now to do a detailed analysis of the data, but I do see some things that make me go "hmmmm".

 

Rather than comment, I'd like for you to get the live data once more, but after the engine is warm enough for the system to be in "closed loop". "Fuel Sys 1" will indicate "CL" (not "OL", which is "open loop"). Once it's "CL", note all the live data at idle, and also the following:

 

Observe the "O2SB1 S (V)", and note the readings over time. Let us know the lowest and highest, and if there's a tendency to stay near a certain range of voltage.

 

Get a reading of the MAP at idle speed and also around 1500 and 2500 rpm (in neutral). Same for the fuel trims (STFT and LTFT). Hold at each speed for several seconds until the LTFT reading is somewhat stable.

 

Find a helpful passenger, take a short road trip, and get them to compare "Veh Speed (MPH)" with what the speedo says at various road speeds.

 

Let's see where that leads us.

 

EDIT: In the morning, when you first start the engine, compare the ECT (Engine Coolant Temperature) and IAT (Intake Air Temperature) live data readings. They should be almost the same with the engine cold.

Edited September 18, 2010 by OB99W

[Fairtax4me]

!st code: PO304,

Freeze Frame Data:

- Fuel Sys 1: "CL"

- Calc Load %: "7.8"

- ECT (F): "132"

- STFT B1 (%): "-14.8"

- LTFT B1 (%): "-1.5"

- MAP (inHg): "18.8"

- Eng RPM: "772"

- Veh Speed (MPH): "0"

2nd code: PO302

3rd code: PO303

4th code: PO301

5th code: PO113

6th code: PO302 with "Pending" blinking

7th code: PO304 with "Pending" blinking

Good stuff here.

The ECT throws me a bit. Was this a cold start or had the car been driven previously that day before connecting the scanner?

 

A pending code is a fault that has been detected, but has yet to illuminate the MIL because it is a "two trip" fault. It has to re-appear on two consecutive "drive cycles" before it will illuminate the MIL, otherwise it will be erased.

I think it is safe for you to delete any current, stored, or pending codes and start fresh. This way the scanner will store freeze frame data from the most current code when that code is triggered.

[OB99W]

The ECT throws me a bit. Was this a cold start or had the car been driven previously that day before connecting the scanner?

Since the data you quoted was freeze frame at the time the P0304 was set, I don't think we know when or under exactly what conditions that occured.

 

What's interesting about the ECT readings is that in the freeze frame data, at 132 deg F the system was running closed loop, while in the live data, at 170 deg F it was open loop. That makes one wonder what the ECU was "thinking" (unless the "170" is an error, and was either "107" or "110").

 

Hopefully the closed loop live data and the additional data points I asked for will help clarify what's going on.

[2000 Legacy]

Hi,

 

I see I posted my message twice last night, sorry about that. I re-did the Live Data this morning after driving to work (about 30 miles) and again driving home (30 miles). This is what I got:

 

AT 5:45 AM

 

Fuel Sys 1: CL

Calc Load (%): 4.7 (9.2 at 2200 RPM's)

ECT (F): 200

STFT (B1) %: -8.5 (.7 to 3.1 at 2200 RPM's)

LTFT (B1) %: -11.7 (-10.9 at 2200 RPM's)

MAP (inHg): 12.9 (8.3 at 2200 RPM's)

RPM: 660

Veh Speed: 0

Spark Adv: 10, 9, 5, 7 (jumped around)

IAT (F): 87

MAF: 0.510

TPS: 0

O2S B1 (S2 (V): 0.860

STFT B1 (S2) %: 0

OBDSup: OBD2

O2S B1 S1 (V): 3.752

EQ Ratio 11: 1.031

 

AT 9:30AM

 

Fuel Sys 1: CL

Calc Load (%): 5.0 (9.8 at 2000 RPM's)

ECT (F): 194 (192 at 2000 RPM's)

STFT (B1) %: -7.8 (-3.1 at 2200 RPM's)

LTFT (B1) %: -11.7 (-10.9 at 2000 RPM's)

MAP (inHg): 12.6 (8.2 at 20200 RPM's)

RPM: 671 (2104)

Veh Speed: 0 (0 at 2000 RPM's)

Spark Adv: 10 (33 at 2000 RPM's)

IAT (F): 86 (89 at 2000 RPM's)

MAF: 0.543 (1.097 at 2000 RPM's)

TPS: 0 (0 at 2000 RPM's)

O2S B1 (S2 (V): 0.815 (0.730 at 2000 RPM's)

STFT B1 (S2) %: 0 (0 at 2000 RPM's)

OBDSup: OBD2

O2S B1 S1 (V): 3.8 to 3.663 (3.791 at 2000 RPM's)

EQ Ratio 11: 1.001 to 0.986 (0.959 at 2000 RPM's)

 

About four hours later I reread your reply and wasn't sure that what I did earlier was correct so I went out and plugged in the 3130 and started the car and took the following readings in 5 minute increments (1:13 PM, 1:18 PM & 1:23 PM):

 

Fuel Sys 1: CL (I was surprised, I thought this would be OL when I first started the car)

Calc Load (%): 7.4, 4.8 (9.8 at 2000 RPM's)

ECT (F): 149, 186 (194 at 2000 RPM's)

STFT (B1) %: -3.9, -7.8 (1.5 at 2200 RPM's)

LTFT (B1) %: -11.7, -11.7 (-15.6 at 2000 RPM's)

MAP (inHg): 17.4, 12.6 (8.2 at 20200 RPM's)

RPM: 691, 712 (2085)

Veh Speed: 0, 0 (0 at 2000 RPM's)

Spark Adv: 1 to 11, 10 (33 at 2000 RPM's)

IAT (F): 96, 100 (104 at 2000 RPM's)

MAF: 0.773, 0.589 (1.15 at 2000 RPM's)

TPS: 0, 0 (0 at 2000 RPM's)

O2S B1 (S2 (V): 0.910, 0.885 (0.805 at 2000 RPM's)

STFT B1 (S2) %: 0, 0 (0 at 2000 RPM's)

OBDSup: OBD2

O2S B1 S1 (V): 3.763, 3.811 (3.786 at 2000 RPM's)

EQ Ratio 11: 1.013, 0.999 (0.996 at 2000 RPM's)

 

I missed the part about comparing the ECT and IAT early in the morning. If needed I can do it tomorrow morning.

 

As for Fairtax4me's question in Post 105, yesterdays scanner results were from a cold start, the car hadn't been started or driven for 3 days.

 

OB99W, I read your concerns in Post 106 about my results with regard to the ECT. I double checked the Freeze Frame Data, it was 132 in a Closed Loop. I also double checked my rough notes from last night and I had written the ECT results as 170, 168, 161 so I'm pretty sure I wrote it correctly.

 

The other thing I noted today is that the scanner didn't show the last 2 codes (6 & 7 pending) this morning and this afternoon it showed 6. I don't know if that means anything.

 

Sorry for the long write up, I put my results in a excel spread sheet and tried to attach it and cut and paste but niether worked for me. Oh well, thanks for everything.

 

2000 Legacy

[OB99W]

Thanks for retesting and posting the results. You didn't quite do what I asked (I wanted some of the data at both 1500 and 2500 rpm, not at the median value of the two [2000 rpm] ), but for now we've got enough.

 

Most of the readings fall within acceptable ranges. Things that don't:

 

1) Fuel trims should normally be no more than about 5% (positive or negative) if all's right -- the higher (over 10%) negative readings you've posted indicate that the ECU sees the mixture as rich, and is cutting back on fuel (narrowing the injector pulse width).

 

2) MAP readings at idle are high. You can roughly calculate intake vacuum by subtracting the MAP reading from atmospheric (barometric) pressure. Average atm pressure at your elevation is about 29.5 inches Hg. MAP of 12.9" corresponds to roughly 16.6" intake vacuum, while the MAP of 17.4" suggests about only 11.1" vacuum. (The MAP of 8.2 at higher rpm would equate to intake vacuum of 21.3, a much "nicer" number.) I just looked at the MAP readings from your post #103, where the freeze frame shows an even higher MAP reading, 18.8" at just above idle (772 rpm).

 

3) The TPS (Throttle Position Sensor) readings are all "0" (zero), which is acceptable at idle with closed throttle, but not at 2000 rpm, obviously. The above two observations may be directly related to it. It's surprising that no code was set.

 

4) Varying engine timing. For a steady throttle position, this is typically stable. The knock sensor might be picking up something that's causing this. (EDIT: Perhaps more likely, the MAP is indicating to the ECU that the engine load is heavier than it really is, and besides overly enriching the mixture, the ECU is also retarding ignition timing.)

 

So, where does all this lead? MAP and TPS are very closely related as far as the ECU is concerned. If you look at the diagnostic procedure for P0106 and P0121, that becomes obvious. In fact, for P0121 (which is for a TPS range problem), it indicates that if the MAP reading is over 15.75, the MAP sensor should be replaced. I would suggest, rather than immediately going there, you start with a quick voltage check of the TPS. Here's how:

1) Remove the air box from the throttle body so that you can back-probe the TPS connector.

2) Connect the voltmeter negative lead to a good ground.

3) Turn the ignition key on, but don't start the engine.

4) Measure the black lead voltage (should be very near zero, since it's a ground).

5) Measure the red lead (should be close to 5 volts).

6) Measure the white lead while operating the throttle (should vary as it's moved, make note of the reading at closed, one-half, and wide open throttle).

 

Please get back to us with the TPS voltages, and that will determine the next step. Getting a couple more TPS and MAP live data readings with the engine at idle could also help. By the way, a MAP live data reading with the engine not running should indicate atmospheric pressure -- if not, tell us what you get.

 

I have specific other things in mind, but I don't want to make this post any longer than it already is.

Edited September 19, 2010 by OB99W

[samneric]

2) MAP readings at idle are high.

 

I'm as confused by all this freeze-frame data as the rest of us....

 

However, I just found that Wikipedia (again) is my friend

 

http://en.wikipedia.org/wiki/MAP_sensor

 

Steve

[Fairtax4me]

Since the data you quoted was freeze frame at the time the P0304 was set, I don't think we know when or under exactly what conditions that occured.

Should learn by now not to post while I'm dog tired. Actually I literally was dog tired that evening after walking 3 dogs for a family I had been house sitting for all week.

I practically called myself out in that one and didn't even catch it!

[Olnick]

Now that's funny, Fairtax. I accepted what you said . . . until you ratted on yourself!!!

[2000 Legacy]

Sorry I didn't get back to you yesterday, I left the house at 7:30 AM and didn't get back til 7:30 PM.

 

Anyways I just finished getting the following:

 

TPS Voltages: per your 6 step instructions

Black Lead: -0.01 to 0.02

Red Lead: 4.99

White Lead: 0.54 closed, 2.12 1/2 open, 3.80 wide open

 

I then put everything back together and plugged in the 3130 and checked the Live Data without the engine running. The "MAP" was 29.2, the "TPS" was 0.3.

 

I then started the car and within 2 minutes it was "CL". The "ECT" and "IAT" were the same, 68 degrees.

 

The "TPS" was 0.0 at first, 5 and 10 minutes later it was still at 0.0. At 1500 RPM's it was 2.7 and at 2500 RPM's it was 6.6.

 

The "MAP" was 19.1 at first, 5 minutes later it was 18.3 and 5 more minutes (10 min) it was 14.4. AT 1500 RPM's it was 8.8 and at 2500 RPM's it was the same, 8.8.

 

The O2 S B1 (V) were pretty consistant; "S1" ranged from 3.796 at first to 3.728 and the "S2" was 0.005 at first to 0.840.

 

The "STFT B1 (%)" started at 0, then -2.3, -3.1 and then -5.4. The LTFT B1 (%) was -12.5 all the time.

 

I hope this helps, thanks again for everything.

 

2000 Legacy

[OB99W]

Sorry I didn't get back to you yesterday, I left the house at 7:30 AM and didn't get back til 7:30 PM.

 

Anyways I just finished getting the following: [...]

I had written a detailed reply to that latest post (#112), when I remembered something that I previously meant to follow up on. Your post #107 began:

About four hours later I reread your reply and wasn't sure that what I did earlier was correct so I went out and plugged in the 3130 and started the car and took the following readings in 5 minute increments (1:13 PM, 1:18 PM & 1:23 PM):

 

Fuel Sys 1: CL (I was surprised, I thought this would be OL when I first started the car)

Calc Load (%): 7.4, 4.8 (9.8 at 2000 RPM's)

ECT (F): 149, 186 (194 at 2000 RPM's)

 

This could provide an important clue:

Were the first readings (at 1:13) taken immediately upon starting the car?

(Or had the engine already been running for 5 minutes at 1:13?)

[2000 Legacy]

HI OB99W,

 

Yes the reading I took at 1:13 PM on 9/18/10, Saturday were taken "immediately upon starting the car". The engine had not been running for 5 minutes at 1:13 PM. Thanks.

 

2000 Legacy

[OB99W]

HI OB99W,

 

Yes the reading I took at 1:13 PM on 9/18/10, Saturday were taken "immediately upon starting the car". The engine had not been running for 5 minutes at 1:13 PM. Thanks.

 

2000 Legacy

In that case, you were right to note that it was unexpected for the system to be "CL". The ECU's determination of whether to be "OL" or go "CL" is based primarily (although not exclusively) on the temperature it sees from the ECTS. After four hours of not running (and assuming an under-hood ambient temp of no higher than 96F, what the IAT indicated), it strains credibility to believe that the engine coolant was still at 149F (what the ECT reading was).

 

Other readings have also been somewhat erratic, or at least not easily explained, and I know that you've replaced the ECTS. That leaves either an intermittent problem with the ECU itself, or connection problems as possible causes.

 

In my post #38 of this thread I mentioned the problem with corrosion and contamination of the multi-pin engine-to-bulkhead harness connectors. The 20-pin E2/B21 mating connectors are where the MAP, TPS and ECT sensors are routed. Poor contact and leakage conduction due to salt contamination in that and E3/B22 have caused all kinds of weird problems that made diagnosis difficult. If you haven't already done so, I would suggest that you disconnect the E/B connectors and inspect/clean the contacts. Water is best for salt removal, alcohol works for drying afterward. I use 70% isopropyl alcohol (drugstore "rubbing alcohol") in a spray bottle. It works well because the 30% that's water can dissolve salts, while the 70% alcohol is a drying agent. Spray them, wait 1/2 a minute, spray again, repeat several times. If you see anything greenish coming off, keep spraying. Once the connectors are clean, they need to be thoroughly dried. A hair dryer or other source of warm (but temperature-limited) air works well. If that's not available, let things air dry in the sun. You also might want to check the B83 ground/shield junction connector.

 

If you don't mind reading another longish (only 7-page ) thread concerning a 2000 Legacy with strange symptoms that eventually had a simple resolution, see http://www.ultimatesubaru.org/forum/showthread.php?t=100611 .

I think it's worth reading to the end, but I might have a slight bias . Although the problem presented itself differently than yours, it may be that the cause is similar. (Perhaps more than coincidentally, note the last paragraph of post #38 in that thread as well.) The OP, rvac99, was in Narragansett, probably no more than 50 miles from Colchester.

[2000 Legacy]

I can't say it enough, thank you so much for all your time, patients, expertise, ect... I love this forum.

 

I read and researched the E/B connectors. Thanks to the link, 2000+FSM that was posted. Again, I love this forum. Just before dark I went and located them. It looks as though theres some type of boot over the connections. So I'll:

 

1) remove the boots.

2) disconnect the E/B connectors.

3) spray both male and female connectors with 70% isopropyl. Or should I use straight tap water first and then rinse with the isopropyl?

4) dry them with a hair dryer.

 

Is the B83 Ground/Shield Junction by the ECU inside the car on the passenger side? What are we looking for here, the same as the E/B connectors, corrosion?

 

Do I need to disconnect the 3 connectors at the ECU? I thought I had read rvac99's post where he had to but then thought that maybe he was doing more testing.

 

WOW, what a coincidence with his post 38 and this one. I enjoyed reading all 7 pages. I appologize for not checking this then. I guess I didn't understand where these connectors were, but after researching the FSM things look clearer. Like I mentioned before, I'm no mechanic, nor am I electronic technician.

 

I probaly won't be able to get to this until the weekend sometime but I will post my findings as soon as I can. Thanks again.

 

2000 Legacy

[OB99W]

I can't say it enough, thank you so much for all your time, patients, expertise, ect... I love this forum.

You're welcome, although love is a bit stronger emotion than perhaps warranted.

 

 

I read and researched the E/B connectors. Thanks to the link, 2000+FSM that was posted. Again, I love this forum. Just before dark I went and located them. It looks as though theres some type of boot over the connections. So I'll:

 

1) remove the boots.

I'm not sure that you've correctly identified the proper connectors. The ones we want are not typically booted. One is grey, the other brown, and they should be about as far back as the throttle body, but down on the passenger side near the rear of the engine, on a bracket roughly behind cylinder #3.

 

See the MY02 wiring folder, and open the "Bulkhead Wiring Harness (In Engine Room)" PDF. Page WI-168 lists the connectors, and WI-169 shows a (difficult to use ) location diagram. The "Engine Wiring Harness and Transmission Cord" PDF shows the mating connectors on page WI-178.

 

 

2) disconnect the E/B connectors.

3) spray both male and female connectors with 70% isopropyl. Or should I use straight tap water first and then rinse with the isopropyl?

 

If they look particularly bad, use water first. If not, rubbing alcohol alone should be adequate.

 

 

4) dry them with a hair dryer.

 

Is the B83 Ground/Shield Junction by the ECU inside the car on the passenger side? What are we looking for here, the same as the E/B connectors, corrosion?

Yes, it's near the ECU. It should be a 12-pin, inline, blue connector. See "Bulkhead Wiring Harness (In Compartment)", page WI-174. It's shown on the diagram right near B134, B135 & B136 (ECU connectors). Because it's an interior connector, it's less prone to corrosion, but worth looking at just to be sure.

 

 

Do I need to disconnect the 3 connectors at the ECU? I thought I had read rvac99's post where he had to but then thought that maybe he was doing more testing.

You can leave the ECU connectors alone (at least for now ).

 

 

WOW, what a coincidence with his post 38 and this one. I enjoyed reading all 7 pages. I appologize for not checking this then. I guess I didn't understand where these connectors were, but after researching the FSM things look clearer. Like I mentioned before, I'm no mechanic, nor am I electronic technician.

There's no need to apologize. You've had so many ideas thrown at you that I'm sure it became overwhelming. Those connectors are how all the engine sensors connect to the ECU, and they're vulnerable to road-salt-contaminated water exposure. That makes them worth checking, especially when there are diagnostic readings that don't clearly point to other causes. The misfire codes you're getting aren't specific to a cause, although the code for the front A/F (O2) sensor that popped up a couple of times still might mean it should be replaced.

 

 

I probaly won't be able to get to this until the weekend sometime but I will post my findings as soon as I can. Thanks again.

 

 

2000 Legacy

Okay. I wish I could assure you that cleaning those connectors will resolve everything, but at least the job is neither difficult to do nor expensive, and there's a history of them causing problems.

http://set2music.files.wordpress.com/2009/10/fingers_crossed.jpg

[Fairtax4me]

I then started the car and within 2 minutes it was "CL". The "ECT" and "IAT" were the same, 68 degrees.

Was that 68°F or C?

The O2 S B1 (V) were pretty consistant; "S1" ranged from 3.796 at first to 3.728 and the "S2" was 0.005 at first to 0.840.

Maybe consistent, but high by 3 V. O2 sensor output shouldn't be more than 1.0V during normal operation. Maybe OB has a good explanation for this?

 

Now that's funny, Fairtax. I accepted what you said . . . until you ratted on yourself!!!

 

I work at a car dealership... I have to be honest at some point during the day!

[Ricearu]

hmmm the O2 situation is wierd.

 

Reading back on older posts, I agree with ob99w that the temp sensor is off kilter. There should be 2 ECT sensors. One for the gauge, one for the ECU. which one did you replace?

Edited September 22, 2010 by Ricearu

[OB99W]

Maybe consistent, but high by 3 V. O2 sensor output shouldn't be more than 1.0V during normal operation. Maybe OB has a good explanation for this?

Being biased up like that, one might think there could be leakage from the sensor's heater, or that the ECU had a problem. However, it's been shown a replacement ECU (admittedly, a used one) didn't change the voltage, and that with a new sensor, things worked okay even though the voltage remained high. See http://www.ultimatesubaru.org/forum/showthread.php?t=66744 (and then maybe you can explain it to me ).

 

Actually, the consistency of the reading, in conjunction with the code occasionally thrown, is why I've mentioned that the front sensor might need to be changed. Given the various conditions under which data was read, I'd have expected to see more swing. The O2 sensor isn't wired via the connectors that I've asked 2000 Legacy to check/clean, but some grounds are. Once that's been done, we can evaluate what else to consider.

Edited September 22, 2010 by OB99W

[OB99W]

[...] There should be 2 ECT sensors. One for the gauge, one for the ECU. which one did you replace?

Earlier models used two sensors (a single terminal one for the gauge, and a two-terminal one for the ECU), but the 2000 and later have a combined sensor with three terminals.

[OB99W]

2000 Legacy,

 

As we've already discussed, some of the OBD-II live data readings you're getting are erratic/inconsistent. I've suggested cleaning the E/B connectors because previous experience has shown contamination and corrosion there to be a cause of some very strange problems that show up in OBD-II data and even set spurious trouble codes.

 

However, in order to perhaps "cut to the chase" on your problem, I'm going to fill you in on some things you might not know, and suggest some steps to take if cleaning the E/B connectors doesn't help.

 

Subaru had problems with both the front A/F sensor and ECUs on the 2000. There were recalls for the sensors, and ECUs got reflashed and/or replaced. I don't know if your car was subject to, or had those recalls applied in the past.

 

My suggestions if the upcoming weekend's efforts aren't helpful:

1) Have your VIN number handy.

2) Call Subaru of America at 1-800-782-2783

3) Tell them that that the way the engine is running/stalling you're afraid to let others drive your car.

4) Tell them that you know of the 2000 model A/F sensor problems and recall(s), and that your A/F (O2) sensor readings are out of spec.

5) Ask if your car has any "open recalls" on it (they'll ask for the VIN).

6) If the A/F sensor and/or ECU are covered, ask for written confirmation (so that you can go to a dealer and have the problems addressed at no charge to you).

7) If SoA can't/won't help, replace the front A/F (O2) sensor.

 

I've been somewhat reluctant to blame the front A/F sensor because you've reported that the problem is worst with a cold engine, when the engine management system should be "OL" and ignoring that sensor. However, we've seen from your posted data that the ECU is going "CL" very early (inappropriately?), which means that it could be affecting running conditions even with a relatively cold engine.

 

Please let us know how things go.

[2000 Legacy]

Hi OB99W and anyone else interested,

 

I cleaned the E/B Connectors as well as the B83 ground connector. They all looked good, no sign of corossion. I sprayed them good with the isoprpyl, hair dried them and let the car sit for 24 hours. I took it for a ride and the problem (stalling) still ocurred.

 

I checked for recalls, my records and found that on 12/26/2002 with about 46,000 miles Subaru performed WXV79, Engine Control Module. From what I can tell on my invoice they replaced the ECM with a remanufactured one. At the time when they did this the car would still run when the key was removed while the shifter was in reverse only. The invoice also said that the check engine light was on and they said it was misfiring, they replaced plugs and wires. Could the ECM have gone bad again? Is there a way that I can test it?

 

I called SOA yesterday and explained my problem and how I went to a dealer about 1 1/2 years ago and how I have been working with USMB since to resolve the problem. I mentioned how the car is unsafe to drive, how the A/F (O2) sensor is out of spec. They said that there are no open recalls. They recommended that I go back to any Subaru dealer, have them diagnois it, then call SOA back with the dealers findings where at that point SOA would make a determination as to what they could do for me if anything. They gave me a a case number.

 

I'm reluctant to do this becuase either way I'm sure I'll end up paying more. I've called around for the A/F (O2) sensor, the cheapest OEM I can find is about $140.00 on-line. So I think thats the way to go. How hard is it to replace this sensor? I've heard they can be seized in pretty good. Are there any tips and tricks? Do I need a special socket?

 

I start my Adult Education Auto Class this week and was hoping to put the car on a lift to check it out and maybe replace it next week.

 

Any other thoughts or ideas? Thanks for everything.

 

2000 Legacy

[OB99W]

Well, the E/B connectors aren't hard to deal with, and eliminating potential problems with them just makes the remaining possibilities more likely.

 

ECUs don't fail very often. The only reason I mentioned it is that there's a history with the 2000 Legacy. If there was an open recall, then it would have made sense to let SoA see to things.

 

Since SoA says there are no open recalls, I agree that going to a dealer will probably result in more charges to you. Because you've had a code for the front A/F sensor pop up previously, and it has lots of miles on it, and the readings aren't looking that good, it's probably worth the $140 risk. (Yes, I know, that's easy for me to say. ) An "interesting" experiment (if you're so inclined) is to disconnect the front sensor and see what change there is in operating conditions. You will get a code due to the disconnection, but that can be temporarily ignored.

 

Removing the sensor can be a challenge, especially one that's been in there a long time. The key is don't force things so much as to damage the threads. These links cover the situation fairly well:

http://www.ehow.com/way_5380534_ways-remove-oxygen-sensor.html

http://www.subaruoutback.org/forums/66-problems-maintenance/14904-2000-obw-p0136-disconnected-front-o2-sensor.html

A new sensor should come with some anti-seize lube, typically already applied to the threads.

[2000 Legacy]

Thanks again OB99W for the insight and the links. When you say disconnect the O2 Sensor do you mean disconnector unplug it from its electrical connection or remove the sensor entirely? If I do so do you think it would harm anything if I was to disconnect it, drive home 25 miles, let the car sit a week and then drive another 25 miles to either replace the sensor or reconnect it? If all I need to try this experiment is to unplug the electrical connection, how accessible and where is it? Thanks.

 

2000 Legacy