OB99W Posted November 20, 2010 Share Posted November 20, 2010 [...]I’ll also look at rechecking the “fuel pressure” with the new FPR as well as the vacuum. Is there any other way of checking the return line other than what I did (blowing air at the FPR and listening at the fill pipe for the gas tank)?[...] If the fuel pressure is okay (checked in the manner previously described), then the return line is fine. If the pressure is too high with the new FPR, then the line is likely at least partially obstructed. (Obviously, if air passed through the line to the tank, it couldn't be completely blocked.) Physical inspection might reveal damage. Another thing mentioned in Post # 198 was “valve adjustments”, I’m not aware that the car has had any and like I mentioned in the beginning is that we bought this car brand new in 2000. I have to admit I’m not familiar with this and do not know what is involved with valve adjustments. Unfortunately, it's probably not something you'd be inclined to do yourself. To see what's involved, look at the FSM section "Engine", file "valve clearance.pdf". Before the 2003 models, Subaru specified a 105,000 mile interval for checking/adjusting the valves on engines with mechanical lifters (hydraulic lash adjusters, or HLAs, don't require adjustment). You might find these interesting: http://www.mastertechmag.com/mtwp/2009/April/image/pdf/IS_200904_subarutrainvalve.pdf --or-- http://www.furi-dorifto.com/tech/Subaru_dox/Valve07MayEW.pdf Quote Link to comment Share on other sites More sharing options...
hankosolder2 Posted November 20, 2010 Share Posted November 20, 2010 As for checking the “duty cycle” the ECU is applying to the IACV, I’ll have to look around to see if someone has an oscilloscope, not that I’d know what to do with it, but I’ll cross that bridge once I get ahold of a scope. There are a few things I need to look up that I didn’t understand; like cam lobe, algorithm and kludge. 2000 Legacy. Happy to help you with a few of those terms. I'd say your first port of call would be to recheck the fuel pressure though- you know how to do it and it's important to eliminate that before wasting time going down diagnostic blind alleys. -Kludge is (i believe) a computer derived term for an inelegant work-around or half-assed way of fixing a problem. -algorithm in this context refers to the math or internal equations the engine control computer uses to deduce how much fuel the injectors should supply under a given engine operating condition i.e. the computer takes the input from the MAP sensor, coolant temp sensor,o2 sensor, throttle position sensor etc and factors all those together (using an algorithm) to decide injector pulse width and thereby amount of fuel needed for the amount of air going into the engine. As to cam lobe, a picture is worth a thousand words there. Nathan Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted November 20, 2010 Share Posted November 20, 2010 A cam lobe is the part of the cam that looks like an egg. It's what opens the valve. Quote Link to comment Share on other sites More sharing options...
2000 Legacy Posted December 3, 2010 Author Share Posted December 3, 2010 Hi everyone, I’m sorry that it has been a while; we didn’t have our adult auto class last week due to the holiday. Anyways, I was able to borrow the same fuel pressure gauge to recheck the pressure since we replaced the Fuel Pressure Regulator (FPR). Here are the results: The results were similar to what we posted in Post 169, Page 17 of this thread; however it was noted this time that the gauge was off, it read 5 PSI without being hooked up. So we assumed that it was off when we did it the last time as well. We checked the fuel pressure readings per the instructions per Post 164, Page 17. I started the car, the readings were: - Vacuum = 15 PSI bouncing between 14 – 18 PSI. - Fuel Pressure = 41 – 42 PSI I then let the car warm up for 5 minutes, the readings were the same. I don’t remember if the vacuum bounced that much the last time we checked it. Then we removed the vacuum hose at the FPR and plugged it with my finger, leaving the FPR open where the hose plugged into. The readings were the same for the vacuum and the fuel pressure went to 49 PSI. We then shut the car off and monitored the fuel pressure for about 10 minutes. It seems to start at 45 PSI and then rise to 46 PSI. Please keep in mind the fuel pressure readings above are 5 PSI too high. I started going through all my receipts related to this problem and found that this problem seem to start at about 180,000 miles, about the time that I replaced the battery. Could this have affected the ECU? Also, I checked the gas mileage the other night, it was 18.78 mpg. I’ll have to check it again because that doesn’t seem to be that great considering we changed the FPR, O2 Sensor and fuel filter. I still haven’t been able to locate an oscilloscope but will continue to look. I mentioned adjusting/checking the valves, someone had asked me what type I had, I wasn’t sure. They also weren’t aware of what could really be done with them. I get the impression that this would be too big of a job for me and that it may not be worth it. Oh well, please let me know your thoughts/ideas. Thank you everyone for your help and expertise. 2000 Legacy Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted December 3, 2010 Share Posted December 3, 2010 Valve clearance adjustment should be fairly easy. That engine is SOHC (right?) so should have the solid lash adjusters on the rocker arms. That procedure should be in the FSM. Fuel pressure sounds about right. Maybe a hair high at 36psi? I thought it was supposed to be like 32. But we now know the gauge you used isn't entirely accurate. Quote Link to comment Share on other sites More sharing options...
2000 Legacy Posted December 4, 2010 Author Share Posted December 4, 2010 I found the procedure for the valve adjustments in the FSM. Thanks, I'll look into it. 2000 Legacy Quote Link to comment Share on other sites More sharing options...
samneric Posted January 6, 2011 Share Posted January 6, 2011 What's the latest on this? Curious now and thread has been silent for a while!!! Steve Quote Link to comment Share on other sites More sharing options...
2000 Legacy Posted January 7, 2011 Author Share Posted January 7, 2011 Hi everyone, I just spent the last 20 minutes looking for this thread when I should have looked to a more recent date. Anyway the reason why I was looking for it was to first, sincerely thank everyone who helped me, responded to my posts, read my post and for the people that make this forum possible. Your time and expertise is very much appreciated. I have since been on a few other forums and none are half as good as this one. The other reason was that I wanted to let everyone know that I have given up and traded the car in. As much as I wanted to keep it and solve the problem I could not justify to my wife and son, whose car it was in registering and putting another car in the driveway. I was hoping to get another Subaru but it didn't work out that way. Maybe some other time. Again, thank you all. 2000 Legacy Quote Link to comment Share on other sites More sharing options...
eulogious Posted January 7, 2011 Share Posted January 7, 2011 Too bad you gave up on the subaru, but you did try freakin' hard to keep it! But I understand wanting a reliable car, and having a stalling car that you can't figure out isn't reliable at all. But good on you for trying What type of car did you end up getting? One thing that I have noticed is that alot of the information found here can apply to any application, you just need to be creative sometimes, but the bulk of the info is useful for any car. I have used some of the skills I have learned here to work on fords and kias, so feel free to search around here if you need some answers. Lots of smart people on this board. Hopefully you will own a subaru again one day! Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 8, 2011 Share Posted January 8, 2011 Guess we'll never know now. After putting that much time and effort into something I would have been dead-set determined to find the problem and fix it. But there is a lot of risk in driving family around in a car with an unpredictable stalling problem. I hope your new vehicle gives you years of reliable service. What are the chances someone else pops up on here in a month or so asking the same questions? Quote Link to comment Share on other sites More sharing options...
tforce Posted January 8, 2011 Share Posted January 8, 2011 Didn't bother reading the whole thread but I did have a similar problem with my 2002 Lego. Car would try to stall sometimes when I pressed the clutch in but corrected itself before it died. Turned out to be a combo of a bad IACV and a fried shunt in the ECM. Replaced both and it pretty much went away. Every now and then it will throw a CEL with the same code but without any stalling or any other issue.....just throws a code randomly. Turns out that some of the ECM's were programmed with too narrow of a parameter set associated with the IACV. Supposedly you can get your ECM flashed to widen the parameters and cure it. But it's really hard to find a dealer that knows about it. Gresham Subaru in OR had to dig into their troubleshooting laptop to find any info on it for me....wasn't on any bulletins, etc. Haven't bothered yet cuz it only throws the code once or twice a year and caused zero problems.....no reason to spend the money. Quote Link to comment Share on other sites More sharing options...
2000 Legacy Posted January 13, 2011 Author Share Posted January 13, 2011 Yeah I too am sorry that I gave up, I thought for sure we could fix it. It's just that it was occupying a lot of my time and thought. Like I said, I couldn't justify registering and insuring another vehicle. We picked up a 1999 Honda Civic EX with 127,000 miles on it. It was a one owner car, very clean with car fax and maitenance history. It's real clean and will be a good car for our oldest son who will take it to college next week. If someone does have the same problem that we had with our 2000 Legacy I'd really love to hear what the cuase is. Hopefully nobody has to go through what we went through. Thanks again everyone for the help. 2000 Legacy Quote Link to comment Share on other sites More sharing options...
jcsvx Posted January 21, 2012 Share Posted January 21, 2012 this seems related to a problem we have seen a loose balancer knocks slightly causing knock sensor to retard timing until engine dies below is our fix OK we have fixed this problem on three different 2.5s in the last year all three have had loose front balancers the bolts were tight but bottomed out in crank the key-way and key were worn and had to replace key on all three and new washer and shorten bolt one thread (grinder) the loose balancer causes noise and the knock sensor retards the timing until it missfires and turns on cel. Hope this fix works for you too Joe Quote Link to comment Share on other sites More sharing options...
fixingrusinc83 Posted January 23, 2012 Share Posted January 23, 2012 unplug the brown 2 pin connector for the nuetral safety switch, clear codes and I think your problem will be gone. Quote Link to comment Share on other sites More sharing options...
jcsvx Posted January 23, 2012 Share Posted January 23, 2012 Re: 98 Legacy misfiring on all four cylinders; drives fine I thought JCSVX was full of it but I just took off my harmonic bal and the key was half sheared Replaced it and drove 45 miles with no problem longest drive without light in a month!!! Re: 98 Legacy misfiring on all four cylinders; drives fine thanks Joe our local dealer had replaced (bad loose) timing belts in the past and thought that was what was fixing the problem but one of the Mechanics remembers having to change the key on at least one of the jobs. this may not fix all of them but it has fixed several Quote Link to comment Share on other sites More sharing options...
jcsvx Posted January 23, 2012 Share Posted January 23, 2012 Re: 98 Legacy misfiring on all four cylinders; drives fine Tim this also explains why replacing headgaskets has fixed some of the cars because they have to take timing belts of and why a valve adjustment can fix if they use crank pulley bolt to rotate engine. it will tighten the pulley. OH THE NON BELIEVERS Quote Link to comment Share on other sites More sharing options...
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