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2000 Legacy stalls when clutch is depressed


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#76 2000 Legacy

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Posted 06 September 2010 - 04:33 PM

Hi OB99W, Mr. Carb and anyone else who can help,

I finally had a little time when I could recheck the Vacuum Readings you suggested OB99W. In doing so I first checked the check engine light, at first it was just P0301 but when I finished I had all four cylinder misfires.

1) First I warmed up the car, about 15 minutes.
2) Then disconnected the hose at the intake manifold from the brake booster, it read 18-18.5.
3) Tried the "Air By-Pass Hose" on the Throttle Body and got nothing. I thought that this is what DaveT and I had done back in March. Reconnected it.
4) Tried the smaller vacuum hose on top of the intake manifold, just to the right of the throttle body/center of it (looking into the engine compartment) and got 18-19 with it removed from the intake. When the fan kicked in it dropped to 18-17.5. Note, I just let the other end of the hose hang.
5) With the brake booster hose off at the manifold and taped with the gauge still at the throttle body I got 18-18.5. When I took the tape off the engine seem to run smoother and steady and the gauge seemed steadier at 18.
6) Reconnected the brake booster hose.
7) I then connected a tee to the throttle body connection port, the gauge and the other end of the hose that was hanging in "4)" above and got 19-19.5 at first and then dropped to 18.5.
8) I took the brake booster off and the engine ran smoother and the needle on the gauge was steady at 19 and dropped to 18 with the fan on.
9) Plugged the brake booster hose a the maniflod with a rag an my finger, the gauge dropped below 15 and stumbled, almost stalled but slowly it built up to and held at about 18-18.5.
10) I then took a piece of hose to try and listen for hissing, couldn't find anything consitant.

Sorry for the long story, its just that I'm not too sure about what I'm doing. But based on what I see I think the vacuum is fine although I'm not 100% sure.

I have to appologize to Mr. Carb, I didn't see your picture until today. Apparently my work doesn't allow those to be posted however going online at home I saw it as clear as day along with OB99W's. I haven't pursued the fuel end of it yet. It seems like a lot of work. Also I was wondering if it were a fuel issue wouldn't the car run crappy all the time? Once on the highway and no shifting/clutching is involved the car runs great and seems like it would go forever. This leads to my next quetion:

Would the scan tool pick up this information?

I checked my OBII tool, its a "Actron CP9135". I don't think it does "Freeze Frame Data" or "Live Data". OB99W said he uses "Innova Equus", which model? I've done some research and see I could get the "3130" for $135.00, "3140" for $189.00 and the "3160" for $200.00 from Amazon.com. Would the "3130" be good enough for my abilities or would the extra $50-$70 be worth it in the end? I wouldn't mind spending the money if I know that this tool will be useful down the road, I was hoping that when I bought my Actron that it would be suffient enough. I hate to bother DaveT, he has a lot going on as I'm sure you guys do as well.

Well, thanks for everything.


2000 Legacy

#77 Fairtax4me

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Posted 06 September 2010 - 05:07 PM

. Is there a place where I can rent one or how expensive are they? I tried Advanced Auto and they said that they have the Actron OBII code reader.


Actron does have a scanner that will read live data but it is pretty pricey. You can get a much better scanner from Innova for less money on amazon, as you have already found.

The main advantage to the 3160 is that it reads ABS codes, but that function only works with Big 3 automobiles.
The 3130 should do everything you need, and is upgradeable, so if by chance sometime in the future Innova makes an update for Subaru ABS codes you can buy a patch and load it into the scanner and make it that much more useful.

#78 OB99W

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Posted 06 September 2010 - 05:15 PM

I sometimes have a tendency to incorrectly assume that forum members have certain knowledge. When checking engine intake vacuum, the best port is the one closest to the center of the intake manifold, and a "T" should always be used so that running conditions aren't changed. That is, except in the case of things like the brake booster which aren't related to engine operation, vacuum hoses shouldn't be left dangling.

Before I comment further, just to make sure I understand what was said in points 7 through 9:
The engine ran better (smoother, higher vacuum) with the brake booster hose disconnected from the intake and that port left open, then temporarily faltered (vacuum initially dropped) when the port at the intake was plugged. Is that correct?

#79 2000 Legacy

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Posted 06 September 2010 - 06:54 PM

Thanks FairTax4Me and OB99W for responding so soon. You are correct OB99W, the engine seemed to idle more cosistant and steadier with the brake booster hose disconected at the intake manifold, however when I put my finger/rag over the port it stumbled and almost stalled but didn't. It then seemed to correct itself and the vacuum went back to 18-19. Please note that the needle on the gauge seemed to bounce at normal conditions or when the vacuum wasn't obstructed or when I didn't mess with the brake booster hose. When I say bounce I mean that it was within a range of 0.5, I assume this is becuase of the rough idle. Thanks again.

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#80 Fairtax4me

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Posted 06 September 2010 - 08:28 PM

The fact that the engine runs at all with the brake booster hose disconnected surprises me. Idle speed will tend to increase a bit and smooth out with a small leak. But with a large leak it usually leans out the mixture so much that it stalls the engine.

#81 OB99W

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Posted 07 September 2010 - 12:30 AM

The fact that the engine runs at all with the brake booster hose disconnected surprises me. Idle speed will tend to increase a bit and smooth out with a small leak. But with a large leak it usually leans out the mixture so much that it stalls the engine.

Yes, the results were a little unexpected, which is why I specifically asked 2000 Legacy to verify that my understanding of his findings were correct.

Any significant amount of unmetered ("false") air typically causes the engine to run too lean, and if not stall, at least bog down. The fact that it ran better with the additional air, and bogged when that air was cut off is, ummm, "interesting". It sort of implies that either idle air is inadequate, or idle fuel is too generous for some reason.

I'm going to sleep and see if my mind will work on it overnight. :)

#82 OB99W

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Posted 07 September 2010 - 01:06 PM

Now that my brain is more awake... :)

I'm leaning towards there being insufficient air rather than excessive fuel. The engine's positive reaction to having the brake booster port on the intake left open (effectively a huge vacuum "leak") suggests that idle air is otherwise way too low. Even though in three places in this thread it was stated that the dealer replaced the IAC("motor"/V), and that it didn't help, a malfunctioning IACV would seem to be the most logical culprit. Furthermore, the $250 dealer price quoted seems insufficient for the valve -- that amount is more typical for aftermarket pricing on the internet. I might be wrong, but I suspect that the entire valve assembly did not get replaced.

I was going to describe how to clean the IACV, but I decided to do an online search first, and found a thread that includes a post by porcupine73, explaining the procedure. See: http://www.subaruout...talls-help.html
Be sure to read both pages, especially the last one, which gives the resolution for that particular owner's problem.

#83 2000 Legacy

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Posted 07 September 2010 - 05:14 PM

Hi OB99W, Fairtax4me and anyone else interested,

I really appreciate all your time and effort, thank you. I read your post (80 & 81) this morning at work with my morning coffee and was wondering if I did something wrong yesterday. I took the subie with me today to work and couldn't wait to get home and recheck yesterdays efforts. I drove the car about 20 miles/30 minutes about, pulled the car into the driveway and left it running. I popped the hood, got a pair of pliers out and disconnected the vacuum hose for the brake booster at the intake. Again like I said yesterday the car seemed to idle/run smoother, it didn't stall, the RPM's kicked up to about 1100. I let the car idle for 5 minutes and then reconnected the vacuum hose, the car stalled. I then restarted it and it idled at about 600 RPM's. I then disconnected the hose again, same results.

I rechecked my $370.00 bill from the dealer and it says that they "installed idle air control motor, stalled on roadtest", and from what I remember the Service Advisor had said it would be about $250.00. That was after they finished replacing the fuel injectors for $600.00. I assumed that the dealer would use OEM parts. But who knows what they really did and with what, I could have misunderstood him too.

I don't know if I mentioned it or not or if its important, but I did replace the "Knock Sensor" on 11/26/06 at 144,144 miles. I used a NAPA sensor.

I read and printed "porcupine73's" post on 3/22/08, 7:59 AM and paid special attention to his point no. 3. Sounds easy enough and cheap enough, I just need to get some "Throttle Body Cleaner" and some time. I may not be able to get to it until Sunday.

I also read your last sentance; "read both pages, especially the last one, which gives the resolution for that particular owner's problem". I did have that P0133 code twice back in 2008. Front O2 Oxygen Air Flow Sensor, is there a way we can test this before I buy it for $139.00 at subarupartsforyou.com? Or should I try an aftermarket/used? Or just go for it if cleaning the IACV doesn't work?

Again thanks for everything.
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#84 Fairtax4me

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Posted 07 September 2010 - 09:05 PM

I didn't see this anywhere, has the fuel pressure been checked? Also has the vacuum line for the fuel pressure regulator been checked to see that it is clear of fuel? (a split diaphragm in the FPR will cause fuel to leak into the intake)

Also the car tends to stall more when cold correct? Like in the first 1-3 minutes after starting? Or is it more like 10 - 15 minutes after starting that it does this?

#85 OB99W

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Posted 07 September 2010 - 09:08 PM

In order to hopefully give you confidence we're on the right track, I "played" a bit with my own car this morning. Not that I expected anything much different, but my '99 has about 20.5" of vacuum at idle (with some needle "flutter"), and disconnecting the brake booster hose caused an almost instantaneous stall.

Yes, we apparently can't be sure what the dealer did concerning the IACV, so cleaning the valve is a first step. It might be there are problems with it that are beyond the help of cleaning, but as you mentioned, it's "easy enough and cheap enough". Let's see where that goes before considering anything else.

As to the O2 sensor, we usually suggest replacement of front ones with only OEM Subaru. But let's not go there yet.

The Innova I have is the model 3130. It's hardly my only electronic tool -- there are digital and analog multimeters, scopes, exhaust gas analyzers, etc. -- but being able to see OBD-II live data means that the others get used less frequently.

By the way, would you humor me and see if the idle is affected by removing the oil filler cap? (Considering how air-starved the engine seems to be, I'm wondering how it might affect the PCV.) With the cap off, can you feel a slight vacuum, or pressure, at the oil filler tube?

#86 Fairtax4me

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Posted 07 September 2010 - 09:13 PM

Here's another one I haven't seen. What has your fuel mileage been during the time this has been going on? Is it any different than it was before this started happening?

#87 OB99W

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Posted 07 September 2010 - 10:10 PM

I didn't see this anywhere, has the fuel pressure been checked? Also has the vacuum line for the fuel pressure regulator been checked to see that it is clear of fuel? (a split diaphragm in the FPR will cause fuel to leak into the intake)

Yes, that's the flip side of the coin -- either there's not enough air, or there's too much fuel. We touched on fuel pressure briefly when someone suggested a failing fuel pump as a possible problem, but I don't think it was ever checked, especially at a rail.


Here's another one I haven't seen. What has your fuel mileage been during the time this has been going on? Is it any different than it was before this started happening?

Also a good question -- in particular since a failed FPR could lead to excessive consumption.

So, that leads me to a really wild theory. 2000 Legacy has said "I do notice a burnt smell that I can't pinpoint.", which might be from an overheated cat due to too-rich mixture. He also said "I had replaced the fuel filter that I got from NAPA at about 176,000 miles (I think, it's documented early on). I'm not sure but it almost seems thats when the problems started and have often wondered about changing the fuel filter again." What if the FPR was failing a while ago, but a partially clogged fuel filter had been limiting the fuel delivery anyway? Then, replacement of the filter with one that flowed correctly could cause the FPR's failure to become obvious. :brow:

Or not! :)

Edited by OB99W, 07 September 2010 - 10:16 PM.


#88 Fairtax4me

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Posted 07 September 2010 - 10:25 PM

Hey, that's the kind of wild theory I usually come up with! :lol:


There is also the possibility the valve in the FPR is partially clogged and is raising fuel pressure.

#89 2000 Legacy

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Posted 08 September 2010 - 11:07 AM

Hi OB99W and Faitax4me,

You guys were busy last night, thanks. I'll try to answer your questions/comments in the order they were asked in Posts #84 thru #88;

1) The fuel pressure has not been checked yet.
2) The fuel pressure regulator has not been checked yet either.
3) You are correct, the car tends to stall more when its cold, usually 10-15 minutes and sometimes longer. Also on occasion it will be even longer.
4) I'd be more than happy to humor you OB99W by removing the oil filler cap. It may not be for a few days or maybe even this weekend, but I'll warm the car, remove the cap and see if I feel a slight vacuum or pressure. Did you want me to remove the dip stick and see if I feel the pressure there?
5) I have been checking the fuerl mileage periodically, it seems to be OK however it does vary from 18-21 mpg. I'm in the process of monitoring now and let you know what I get, again maybe this weekend.
6) Yes, that burnt smell is there everytime I drive the car, it sometimes reminds me of a skunk that has sprayed.
7) Changing the fuel filter again has been on my mind for a long time. I guess the reason why I haven't done it yet is becuase one its kind of a pain having the relieve the fuel pressure underneath the dash, although I've talked to some people who don't bother. They say to let the car sit a while and then just disconnect the filter. Since I am inexperienced I tend to follow the book (Haynes). My other thought was that if the fuel filter was clogged wouldn't the car run crappy all the time?

I think my plan will be to clean the IACV with Throttle Body Cleaner, humor OB99W by removing the Oil filler cap and recheck the gas mileage this coming weekend or sooner if I can. Then I'll post my findings for you to diagnois. I also think that I'm going to order the Innova Scan Tool, I can't mak up my mind as to get the 3130, 3140 or 3160. I hate to run into the problem I have now with my Actron which was cheaper but had I known about Live Data and Freeze Frame Data I would have spent the money at that time. Oh well live and learn.

Thanks again for everything.
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#90 Fairtax4me

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Posted 08 September 2010 - 11:57 AM

#2 The FPR is easy to check. It's on the back end of hte passenger side fuel rail. Just pull the vacuum hose off and see if gas drips out. If none comes out, hold it up to your nose and sniff it for traces of fuel vapor. There might be a very faint fuel smell, which is usually nothing to worry about. If it smells like you're at the gas station, you might have a problem. If the hose breaks, it needed to be replaced anyway. Check it well for cracks and dry rot.

#3 10 -15 minutes is that when it stops stalling? Or is that when it starts to occur? The ECU should be in open loop by that point which means O2 sensor output, among other things, will be factored into fuel control. (open loop or closed loop, one of those. I can't ever seem to keep that straight) :-\

#4 I would think if there is any vacuum being built in the crankcase it would show up more at the dipstick than the filler cap. But yes, do check at both.

#5 Is that mileage city or highway (55+)?

#7 I'm also a bit skeptical of the filter, but a quality filter is an inexpensive investment and they're supposed to be changed every couple years anyway.


As for the IAC valve. Subarupartsforyou lists MSRP the valve P# 22650AA21B for manual trans car at $187. Add a few hours labor (which is ridiculous because it only takes 30 minutes to change), plus some shop costs, and I think you get pretty close to that $370 bill.

#91 OB99W

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Posted 08 September 2010 - 12:34 PM

I don't see a reason to replace the fuel filter, and wasn't suggesting it. If anything, the engine might be seeing an overabundance of fuel.

18-21 MPG is reasonable for local driving, but if there's any significant amount of highway travel, it's somewhat low. The cause could be anything that can affect A/F ratio, including a lazy front O2 sensor. But let's keep our focus narrow for now. Cleaning the IACV and looking into (and smelling :)) the FPR vacuum line are relatively easy/inexpensive things to do.

As much as I like good tools, since money is a consideration I'd suggest holding off on the scan tool purchase a bit longer, until we exhaust things that can be done without one. In looking at the comparison chart at http://astore.amazon...tail/B000KID31K , I don't see an advantage in the models above the 3130 for your current vehicle. If you have something else in mind, that might change things.

#92 Fairtax4me

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Posted 08 September 2010 - 10:26 PM

Man those have come down since I last looked at them. I was hunting for wheels and tires for my truck or the Subaru but a nice scan tool for $135 and free shipping... :eek:

Anyway [/Offtopic]

Agreed, a scan tool might answer a few questions, or it might not. I always like to try the easy (cheaper) stuff first.

For some reason there isn't a thread on how to clean the IAC valve in the USRM. Not that I could find at least. I know there are threads around here somewhere about how to do it, but my search skillz are "teh suk". :-\

#93 2000 Legacy

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Posted 12 September 2010 - 06:57 PM

Hi OB99W, Fairtax4me and anyone interested,

I apologize for not responding sooner but today was the first day I was able to get to your reccomendations. Thanks again for everything. This is what I diid this afternoon:

1) Checked the gas mileage: 19.6 mpg around town/back roads, this also includes the idling in the driveway last weekend checking the vacuum. Yesterday and today I put a little over a 100 miles on it, all highway and checked the mileage and got 22.8 mpg.

2) I then pulled the vacuum hose off the Fuel Pressure Regulator (FPR) before stating the car, no "gas drips" and there was a very faint smell if any of fuel vapors. I then started the car with the hose removed and still didn't see any gas drips. The hose itself didn't seem too bad, a small crack about 3/16" long, maybe caused by me when I removed it off the FPR so I replaced the hose anyway.

3) I drove the car about 5 miles pulled into a parking lot and left it running, popped the hood and removed the oil filler cap, I felt some pressure but couldn't tell if it was sucking or blowing. I put a napkin to see if it got drawn in but it didn't. I then left the filler gap off and then removed the oil dip stick, pretty much the same as the filler cap. I then put the filler cap back on, it seemed to draw in but it still didn't seem to make much difference as far as pressure goes. Removing the filler cap and dip stick didn't seem to affect the idle. I then drove about 50 miles and rechecked this test, same results.

4) I then cleaned the Idlle Air Control Valve (IACV) as you suggested per porcupine73's post. I purcased "Throttle Body & Air Intake Cleaner", removed the Air filter housing and disconned the hoses/sensor from it. With a mirror I looked for the port to the Air Intake port expecting to see a round hole, it was elongated/oval shaped and it was before the throttle body plate. With the engine idling I squirted/sprayed the cleaner in. The car stalled. I contined about 3 dozen times. The times it stalled, I restarted it and continued until I finished. I then let the car sit a for about 3.5 hours and took into town about 2 miles, it seemed to be the same. I then drove it about 10 miles to see if it the cleaner needed to be worked in. It seem to idle a little bit better but it still stalled on ocassion.

As for Fairtax4me's earlier question as to when the car stops stalling. It seems to stall less after the car has run for about 15 minutes. However I have driven it for a 1/2 hour and had it stall. I guess I'd have say the longer the car runs the less it stalls.

I think I've done everthing you've suggested and answered all your questions. Please review at your earliest convenience and let me know what you think. Thanks.

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#94 OB99W

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Posted 13 September 2010 - 10:03 PM

1) Checked the gas mileage: 19.6 mpg around town/back roads, this also includes the idling in the driveway last weekend checking the vacuum. Yesterday and today I put a little over a 100 miles on it, all highway and checked the mileage and got 22.8 mpg.

Highway mileage should be higher, probably about 26 MPG or perhaps a bit more. (However, it's hard to get an accurate reading with just a few gallons usage.) If the mileage is actually down, it might indicate that the rich condition is not just a low or idle speed issue. Poor gas mileage can be the result of a failing front A/F (O2) sensor. If the stalling problem was worse after the engine was warm (and therefore running closed loop, using the sensor data) rather than when it's cold, then I'd definitely say the sensor should be changed.


2) I then pulled the vacuum hose off the Fuel Pressure Regulator (FPR) before stating the car, no "gas drips" and there was a very faint smell if any of fuel vapors. I then started the car with the hose removed and still didn't see any gas drips. The hose itself didn't seem too bad, a small crack about 3/16" long, maybe caused by me when I removed it off the FPR so I replaced the hose anyway.

At least it seems that the FPR diaphragm isn't ruptured. Of course, that doesn't ensure that it's regulating pressure correctly. With the vacuum hose off, the pressure will go to maximum. Did you notice any difference in the way the engine was running with that hose on or off?


3) I drove the car about 5 miles pulled into a parking lot and left it running, popped the hood and removed the oil filler cap, I felt some pressure but couldn't tell if it was sucking or blowing. I put a napkin to see if it got drawn in but it didn't. I then left the filler gap off and then removed the oil dip stick, pretty much the same as the filler cap. I then put the filler cap back on, it seemed to draw in but it still didn't seem to make much difference as far as pressure goes. Removing the filler cap and dip stick didn't seem to affect the idle. I then drove about 50 miles and rechecked this test, same results.

I was trying to get an idea of whether the PCV was working. At idle there's less blow-by than at higher speeds, so the PCV should produce a minimal crankcase vacuum. The results are inconclusive. A previous post indicates that the PCV valve has been cleaned, but was the tubing also checked/cleaned?


4) I then cleaned the Idlle Air Control Valve (IACV) as you suggested per porcupine73's post. I purcased "Throttle Body & Air Intake Cleaner", removed the Air filter housing and disconned the hoses/sensor from it. With a mirror I looked for the port to the Air Intake port expecting to see a round hole, it was elongated/oval shaped and it was before the throttle body plate. With the engine idling I squirted/sprayed the cleaner in. The car stalled. I contined about 3 dozen times. The times it stalled, I restarted it and continued until I finished. I then let the car sit a for about 3.5 hours and took into town about 2 miles, it seemed to be the same. I then drove it about 10 miles to see if it the cleaner needed to be worked in. It seem to idle a little bit better but it still stalled on ocassion.

Perhaps a little theory will help with understanding things. When the throttle plate is closed, although it doesn't seal completely, there's certainly insufficient air for the engine to run. It's the function of the IACV to allow a regulated (by the ECU) amount of air to bypass the closed throttle. Assuming that the valve is functioning correctly, it's still possible for passages in the throttle body to be somewhat obstructed. Especially if there really was an improvement after using the cleaner (and not just wishful thinking :)), it's possible that's what's going on. Even though you haven't reported the code, you might want to look at the diagnostic procedure for P0506. If you decide to remove the IACV and/or work on the throttle body, be sure to have new gaskets on hand.

If you aren't inclined to do more cleaning, etc., at this point, then it might be time to invest in a scan tool. The live data from that might point more directly to the cause of the problem.

#95 2000 Legacy

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Posted 14 September 2010 - 05:04 AM

Hi OB99W and everyone else out there,

As far as gas mileage goes, I don't know that we ever got 26 MPG. However it could be that the O2 Sensor has been bad for a while. I drove the car to work this morning, about 25 miles, it stalled the first few times but then seemed to idle better later on or the closer I got to work. Maybe the cleaner needed to work through the system. I'll see if it's any better this afternoon and let you know.

When I pulled the vacuum hose off the FPR I did not see any difference in the way the engine ran or idled.

I'm not sure if the tubing was checked/cleaned on the PVC, I'll do so tonight when I get home from work. What would you use to clean it?

I'll try and look up the procedure for PO506 tonight to see what it says. At the same time I think I'll go ahead and invest in the scan too. It will be a handy thing to have.

Thank you.
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#96 OB99W

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Posted 14 September 2010 - 09:43 AM

The throttle body cleaner might have loosened things up a bit, but in my experience it has the most effect almost immediately after use.

Since the PCV is designed to tolerate petroleum and the like, if you have mineral spirits or something similar around, that should be fine as a solvent. A light coating of oil isn't a problem, just make sure there aren't sludge deposits.

A scan tool will hopefully make the diagnosis less hit-or-miss.

#97 2000 Legacy

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Posted 14 September 2010 - 06:51 PM

I drove the car home from work today and it does seem to run/idle better once it has been warmed up, but it still stalls initially, first 15 minutes or so.

A friend let me borrow a Innova 0303, it looks as though it tells you that there is Freeze Frame Data available but won't give it to you. it looks as though I'll have to get the Innova 3130. Anyways his code reader gave me the following 7 codes in this order PO304, PO302, PO303, PO301, PO113 (a new one which I wonder if that was caused by spraying the throttle body & air intake cleaner into the IACV), PO301 again and PO304 again. I used my Actron code reader and got the same thing but not in the same order; 301, 302, 303, 304, 113, 301 Pd and 304 Pd. Not sure what the Pd is, Pending maybe and I'm not sure if the order makes a difference.

I checked the PVC Hoses (each side of the Air Filter Housing and the Crankcase Ventilation Hose, the Blow By Gas hose and the "Y" shaped fitting).
They didn't seem too bad, the "Y" shaped fitting had some tar like residue ( I guess Sludge deposits) in there but it wasn't clogged, I wiped it out with a rag. As for the hoses, I could'nt really see through them but was able to pass a tie wrap through all of them with no trouble. The hoses them selves have small cracks on the ends but thats it. I'd say if and when we fix the main problem I should probally replace them. I also removed the PVC itself, it seemed fine, I could hear/feel like there were little ball bearings inside of it moving freely.

I printed out the procedure for PO506 and will study it for the time being. I will also plan on ordering the Innova 3130. Thanks for everything.

2000 Legacy

#98 OB99W

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Posted 14 September 2010 - 08:02 PM

Yes, "PD" indicates a pending code. Since the ones that were "PD" are for cylinder misfire, of course that's no surprise.

P0113 definition is "Intake air temperature sensor circuit high input". That would indicate a poor or missing connection to the air temp sensor. If you had it disconnected while cleaning the IACV, that code would be expected. Otherwise, it could be a clue -- the air temp sensor was something I had previously asked about, since it can certainly affect idle adversely if it's not working correctly. It's one of the things the ECU looks at in setting idle mixture, and the IACV duty cycle is a primary control for that.

Okay on the PCV system -- it seems that you've checked it sufficiently.

And ... you're welcome.

#99 2000 Legacy

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Posted 15 September 2010 - 05:01 AM

Is the Air Intake Temperature Sensor the small plug in type connection on the Air Filter Housing? If so I did unplug it to clean the IACV. I've taken that apart before and don't remember seeing a code. As far as I can remember this is the first time I see a PO113.

Anyways I ordered the Innova 3130 last night and hope to have by the weekend. Hopefully like you had mentioned it will get us what we need and tell us more about the Air Intake Sensor, O2 Sensor, etc....

Thanks again, I'll keep you posted.

#100 OB99W

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Posted 15 September 2010 - 09:22 AM

Is the Air Intake Temperature Sensor the small plug in type connection on the Air Filter Housing? If so I did unplug it to clean the IACV. I've taken that apart before and don't remember seeing a code. As far as I can remember this is the first time I see a PO113.

Yes, that sensor (the first two words of which are either in the order "Air Intake" or "Intake Air", depending on who's describing it, by the way :)) is mounted to the air cleaner case/housing. Having it disconnected with the engine running would set the P0113 -- however, if previously you had it off but didn't run the engine, that might be why you didn't set the code.

Edited by OB99W, 15 September 2010 - 01:46 PM.
Corrected typo in diagnostic code number





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