Zomicon Posted June 17, 2006 Share Posted June 17, 2006 Hi all, I just bought a 1997 Subaru Outback (2.5L) with 44K miles for $6200 two weeks ago. Great deal I thought... I had it checked by a mechanic, drove it for a while, and found it to be in great shape. Since I bought it, I have had to have it towed to a shop twice because it stalled after freeway driving and became undriveable. I could start it again but every time I tried to give it gas, it would sputter and die. If I let the engine get cold, everything returns to normal. The details to the best of my knowledge are below. I would greatly appreciate any help you could give me to diagnose the problem. Thanks in advance! Incidents so far: The car drives fine around town. Everything seems to work well until I try to drive it at highway speeds for 10 minutes or so. The idle is good, acceleration is good, slight lifter noise but no knocking. Incident 1: We had previously driven about 30 miles on the highway with no incident and had driven on short jaunts around town with no problems. I had been driving for twenty minutes or so and started down the freeway, after about 5 minutes the check engine light came on. I came to a stop and the engine started to idle roughly, like it was struggling to stay going. I tried to accelerate from stop and the engine died. After that I tried to start it 6 or 7 times. Each time the engine would start and idle okay, but as soon as i pressed the accelerator the engine would die. I tried gentle acceleration and revving it high in nuetral then popping it quickly into drive. Each time the engine died. I let the car sit for 30 minutes, started again, and got the same result. I called a tow truck, which took about 45 minutes and towed it into the shop. By the time I got it into the shop, the car basically ran fine. The shop checked the OBDII codes and found: Knock Sensor and O2 Sensor. I also found there were recalls for alternator and throttle body issues, so I took it into the dealer. Neither one was defective (according to them.) After all this, the car ran perfectly again, with no check engine light, and I was able to drive around town for a few days without incident. Incident 2: After a few days, I changed the air filter and filled up with premium gas. Everything was running perfectly for about 30 minutes. Once again the check engine light came on on the highway. I noticed that when I would slow down, I got the same chugging, low idle behavior. I continued to drive and hit some hilly sections of the highway. I noticed that when I tried to accelerate up the hills, I would push the peddle to the floor but the engine had very little power. After a few seconds, the engine would "catch" and normal power would resume. During this time, the check engine light would come on and off again eratically. A few miles later, I got off the highway and came to a stop. The engine chugged and died. I tried starting it a few times, but was unable to keep the engine going. White / Blue smoke was coming from the exhaust and there was a serious smell of gas. I let the car sit for about an hour and tried it again...same behavior: chugging engine, white smoke, strong smell of gas. The check engine light was blinking as I tried to start it. I called another tow truck, which took about 2 hours to get into the shop. By the time I got there, there was still smoke coming from the exhaust and the check engine light was on, but the car had noticeably improved. By the time the shop looked at it, everything ran fine, there was no smoke, the check engine light was off, and there were no codes. Has anyone seen behavior like this before? The mechanic told me flat out that he is totally confused by the problem and thinks it could be related to the Knock Sensor, Air Flow Meter, O2 sensor, or Coolant Sensor...I don't know even how to diagnose it, let alone fix it, because the only way to make it happen is to drive long enough away from home to the point that I have to tow it back. I read online about a specific knock sensor problem that causes hesitation, and I think this could have something to do with it, but every piece of advice seems to be about Gary's Fix: a home built electrical work-around that de-sensitizes the knock sensor, but I can't find any info on it except for an outdated web page. Please, please help me!!! Incidentally, we were supposed to drive the car up to portland this weekend but we can't move, because we can't drive it more than a few miles. THANKS Quote Link to comment Share on other sites More sharing options...
fnlyfnd Posted June 17, 2006 Share Posted June 17, 2006 Did you put in a new o2 sensor? or knock sensor? Maybe crank postion sensor? The dealer should have to fix the alternator if the recall has not been preformed. I dont know abouth the throttle body - that might have to have a defect in order to fix. Im almost certain the alternator has to be replaced, if it hasn't already. Quote Link to comment Share on other sites More sharing options...
Zomicon Posted June 17, 2006 Author Share Posted June 17, 2006 The dealer should have to fix the alternator if the recall has not been preformed. I dont know abouth the throttle body - that might have to have a defect in order to fix. Im almost certain the alternator has to be replaced, if it hasn't already. The work order I got back from the dealer said "REPLACEMENT NOT NECESSARY" for both throttle body and alternator. I held off on the O2 and knock sensors because my local mechanic told me that the problem could be related to the throttle body, and I should check out the recall before I sprung for the knock and O2 sensors. He also didn't think the knock sensor could cause the kind of behavior I had.... Incidentally, I looked online and found that my vin seemed to fall under the range for recall for the the throttle body even though the dealer told me it didn't need replacing. How can you definitively know if your VIN range requires a given recall? Can that information be found anywhere on the net? Quote Link to comment Share on other sites More sharing options...
fnlyfnd Posted June 17, 2006 Share Posted June 17, 2006 Dealer can tell you if it has been performed. www.my.subaru.com also works - prety sure you have to register, but thats not a big deal. I'd say go to another dealer. What exactly is the recall on the T/B?? The alternator has to be replaced no matter what, unless it already has. I don't know the details on the T/b Quote Link to comment Share on other sites More sharing options...
fnlyfnd Posted June 17, 2006 Share Posted June 17, 2006 http://www-odi.nhtsa.dot.gov/cars/problems/recalls/recallsearch.cfm Thats a lit of the recalls for a '97 outback. You could very well have a ok T/B. Just open up the pdf document on the T/B case and it says...there may not be a sensor in the throttle body. So if you have the sensor then you dont need it to be fixed. I saw nothing about the alternator recall, I have it on my '96...maybe in '97 it was fixed Quote Link to comment Share on other sites More sharing options...
Zomicon Posted June 17, 2006 Author Share Posted June 17, 2006 Dealer can tell you if it has been performed. www.my.subaru.com also works - prety sure you have to register, but thats not a big deal. I'd say go to another dealer. What exactly is the recall on the T/B?? The alternator has to be replaced no matter what, unless it already has. I don't know the details on the T/b Thanks for the advice. I registered on my.subaru.com and am waiting for ownership to be verified so I can check the recalls. The T/B recall is related to a missing part that does not allow a complete return of throttle valve, which causes high idle. Probably not related to my problem, but I still don't like the fact that they told me it didn't need to be done if it did. Re: alternator. I called the dealer where the original owner bought the car, and they did not have the alternator recall performed there. The dealer I took it to did catch the Transverse Link recall and I am scheduled to get that done on monday. I will ask about the alternator then. Wow...4 recalls. Makes me really scared. Quote Link to comment Share on other sites More sharing options...
Zomicon Posted June 17, 2006 Author Share Posted June 17, 2006 In the meantime...does anyone have any thoughts about the behavior with my 97 Outback? If it were you, where would you look first? Zomicon Quote Link to comment Share on other sites More sharing options...
nipper Posted June 17, 2006 Share Posted June 17, 2006 It sounds like you may have a few problems. First one is the knock sensor. That is a pretty clear cut nothing else can cause it fault code. A bad knock sensor can reek havoc with your ignition timing and cause everything you said. the reason why it happens hot is simple. When cold the car is running in an open loop, meaning it is running off of pre determined values for fuel timing etc. The knock ensor, o2 sensor and a few others are ignored at this time. When warm the car goes into closed loop. It is now reading the sensors, and the bad knock sensor is making the car run like crap. Lets clear that up first. Next go to the nhtsa site and check for recalls. If they have not been done on the car, he has to do them no matter how old the car is. Smoke. This car has really low miles on it, which is not always the best thing. Rubber seals dry out, cars are made to be driven, especially sooobies. I would bet if you look under the car you will see oil on the engine (dont blame your mechanic, it may have happened recently with you driving the car) It is possible the previous owner never drove the car longer then 20 minutes at one time. Fix the knock sensor, clear the codes, then come back. Look at the fane belts, what condition are they in (im asking for a reason). nipper Quote Link to comment Share on other sites More sharing options...
Olnick Posted June 17, 2006 Share Posted June 17, 2006 In the meantime...does anyone have any thoughts about the behavior with my 97 Outback? If it were you, where would you look first? Zomicon You might try a new engine coolant temperature sensor--they really mess with the computer's mind! Not too expensive to replace, $20 or so. Good luck. Quote Link to comment Share on other sites More sharing options...
nipper Posted June 17, 2006 Share Posted June 17, 2006 You might try a new engine coolant temperature sensor--they really mess with the computer's mind! Not too expensive to replace, $20 or so. Good luck. that was my second thought, but its defanitly a timing and closed loop/open loop issue. It doesnt really follow the pattern of a bad temp sensor, as they just kill the car. nipper Quote Link to comment Share on other sites More sharing options...
Olnick Posted June 17, 2006 Share Posted June 17, 2006 that was my second thought, but its defanitly a timing and closed loop/open loop issue. It doesnt really follow the pattern of a bad temp sensor, as they just kill the car. nipper Not really--when my temp sensor went bad the car ran, just very poorly. A bad temp sensor could be telling the engine to stay in open loop, which might explain the smoke and gasoline smell--too much fuel when you step on the accelerator. However, IIRC I got a code for the temp sensor. So I could be dead wrong but suggest you look into it, along with the O2 sensor and the knock sensor. Quote Link to comment Share on other sites More sharing options...
Zomicon Posted June 17, 2006 Author Share Posted June 17, 2006 Thanks for the help guys. I have been banging my head against the wall, wondering if the previous owner unloaded a complete lemon on me. I'll start with the knock, coolant and 02 sensors and go from there. Do you think I could just let the car run at idle for a while to try and reproduce the behavior, or do you think it needs to be driven to get it hot enough to make things start going crazy? I would try it myself, but the car is in the shop. The horror of it all, is that my girlfriend and i were planning a surf trip through mexico and beyond, and we bought this vehicle to do it. It looks like we'll have to change our plans, because there is no way I am taking this car down there... I am a complete newby when it comes to cars... Is it possible to change these sensors myself, or do they require a lot of skill / specialized tools and best left to a shop? Thanks. Quote Link to comment Share on other sites More sharing options...
nipper Posted June 17, 2006 Share Posted June 17, 2006 Thanks for the help guys. I have been banging my head against the wall, wondering if the previous owner unloaded a complete lemon on me. I'll start with the knock, coolant and 02 sensors and go from there. Do you think I could just let the car run at idle for a while to try and reproduce the behavior, or do you think it needs to be driven to get it hot enough to make things start going crazy? I would try it myself, but the car is in the shop. The horror of it all, is that my girlfriend and i were planning a surf trip through mexico and beyond, and we bought this vehicle to do it. It looks like we'll have to change our plans, because there is no way I am taking this car down there... I am a complete newby when it comes to cars... Is it possible to change these sensors myself, or do they require a lot of skill / specialized tools and best left to a shop? Thanks. i think your going to have to drive it to reproduce the problem. Also go to an autzone and have them check the codes. Get yourself the haynes manual, you can do these yourself. nipper Quote Link to comment Share on other sites More sharing options...
Olnick Posted June 17, 2006 Share Posted June 17, 2006 I am a complete newby when it comes to cars... Is it possible to change these sensors myself, or do they require a lot of skill / specialized tools and best left to a shop? Thanks. You can do all 3 of those sensors in an afternoon, Zomicon. I'm no great shakes as a mechanic, so if I can do it I'll bet you can! Get yourself a Haynes manual and ask questions here. All you need is a basic metric socket wrench set, some screwdrivers and maybe needlenose and channellock pliers. For the best prices on parts contact Jamie (search here on the board) or call Jason at Auburn Subaru (866-528-5282) and identify yourself as a USMB member. Can't guarantee it'll solve all the problems but it's all stuff that should be done anyway--and it'll save you a few hundred dollars by tackling it yourself. Good luck. Quote Link to comment Share on other sites More sharing options...
nipper Posted June 17, 2006 Share Posted June 17, 2006 You can do all 3 of those sensors in an afternoon, Zomicon. I'm no great shakes as a mechanic, so if I can do it I'll bet you can! Get yourself a Haynes manual and ask questions here. All you need is a basic metric socket wrench set, some screwdrivers and maybe needlenose and channellock pliers. For the best prices on parts contact Jamie (search here on the board) or call Jason at Auburn Subaru (866-528-5282) and identify yourself as a USMB member. Can't guarantee it'll solve all the problems but it's all stuff that should be done anyway--and it'll save you a few hundred dollars by tackling it yourself. Good luck. https://www.subarugenuineparts.com/oe_parts_cat.html thats Jamie Quote Link to comment Share on other sites More sharing options...
Zomicon Posted June 17, 2006 Author Share Posted June 17, 2006 https://www.subarugenuineparts.com/oe_parts_cat.html thats Jamie Thanks so much for the help everyone. I am going to drive the car home from the shop, and I will check out the timing belts, check for oil on the engine, etc. My girlfriend and I are going to tow it on a car carrier on back of the uhaul truck up to Portland and deal with it there. I might try to get to the sensors before then, or I might just wait until we get up to portland. Either way, I will be posting on the board asking for help soon! Thanks Quote Link to comment Share on other sites More sharing options...
Zomicon Posted June 19, 2006 Author Share Posted June 19, 2006 Okay guys. So I have the knock sensor and the coolant temp sensor is coming. When I went to order the O2 sensor, I found that there were two, one for the front and one for the rear. How do you know which one to change? They are $100+ each, so I had hoped to start with one and see how it goes. Which one should I start with that could cause the problems I have been experiencing? Thanks, Zomicon Quote Link to comment Share on other sites More sharing options...
Zomicon Posted June 19, 2006 Author Share Posted June 19, 2006 Smoke. This car has really low miles on it, which is not always the best thing. Rubber seals dry out, cars are made to be driven, especially sooobies. I would bet if you look under the car you will see oil on the engine (dont blame your mechanic, it may have happened recently with you driving the car) It is possible the previous owner never drove the car longer then 20 minutes at one time. Fix the knock sensor, clear the codes, then come back. Look at the fane belts, what condition are they in (im asking for a reason). nipper Thanks nipper. I checked the belts and all the hoses last night and everything seems to be in good shape. I also got under the car last night and checked for oil on the engine, and found a few minor leaks. I noticed a small amount of leakage from the transmission harness--more like seapage, no drips or anything. We had it looked at by a mechanic before we bought, and he noticed minor leaks in the valve cover and rear vent plate. I don't exactly know where those are located, but I checked under the car and couldn't find any drips or oil. I called the mechanic that checked it out and he said the leaks were minor... Quote Link to comment Share on other sites More sharing options...
fnlyfnd Posted June 19, 2006 Share Posted June 19, 2006 I believe that the front one has control on the engine, while the second is just to make sure the cat is working. Wait for someone to verify this, as I don't want to be to blame for a wrong $100 part. Quote Link to comment Share on other sites More sharing options...
nipper Posted June 19, 2006 Share Posted June 19, 2006 I believe that the front one has control on the engine, while the second is just to make sure the cat is working. Wait for someone to verify this, as I don't want to be to blame for a wrong $100 part. thats correct nipper Quote Link to comment Share on other sites More sharing options...
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