cls1000 Posted July 20, 2006 Share Posted July 20, 2006 ok so i have a 98 legacy wagon as my work/winter car. it's a wagon with an auto and a 2.2. it has about 123K on it. anyway i've had it for about 2 years now and the entire time i've owned it it's been doing the same thing, not consistantly but close. when i go to pull out it will hesitate for a few seconds, like there is no gas in the tank, as long as i keep it floored it will take off. and then when coming to a stop it sometimes will idle rough enough to stall the car, and sometimes the idle will just jump right back up to where it's supposed to, but it always starts right up with no problem and generally idels very smooth. so far i replaced the fuel pump, fuel filter, plugs, wires, oem tps sensor, oem knock sensor, air filter, and some other misc. things. the throttle body i took off and cleaned it, you could eat from the inside of that thing...the mass air flow meter is nice and clean, and i'm running out of things to check. i have maintenance records for this car from the day it was bought. always had oil changed right at 3K and all scheduled maintenance performed by the subaru dealer, including the timing belt, up unitl i bought it and experienced this problem. my mileage has gone down from around 20 to like 15 as well. the last thing i did was run a bottle of subaru top end cleaner through it, this made no difference. it also does it with both the knock sensor and egr disconnected so i don't believe them to be the culprit.....anyone got any advice? i love this car but it's driving me nuts!!!!! edit: the car has never ONCE, thrown a check engine light either.... Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 20, 2006 Share Posted July 20, 2006 Might consider replacing the Engine Coolant Temperature Sender. Remove and clean the IACV. Run a bottle of injector cleaner with Techron through the gas tank. Check any electrical connectors you unplugged/plugged--vacuum hoses too. And by all means use the search function here, start with the similar threads at the bottom--lotsa' good info here on the board. Good luck. Quote Link to comment Share on other sites More sharing options...
cls1000 Posted July 21, 2006 Author Share Posted July 21, 2006 well i cleaned out the IAC (it wasn't really all the bad honestly) and put in a new pcv, did nothing.....i'm quickly running out of things to replace....my tps is on the low side (it's .59 with a window of .5 to 1.0v) but i have no more adjustment with out elongating the openings...this is getting so annoying..i drive 4 miles one way to work each day, in the 4 miles today it hesitated like twice and stalled on two other occassions.....anyone ever have problems with crank or cam position sensors? or poossibly the ign. coil or comp??? that's basically what i'm down too...i even tried running sunoco 94 incase the knock sensor was on the sens. side, but this didn't help either... Quote Link to comment Share on other sites More sharing options...
Subaru_for_LIfe Posted July 21, 2006 Share Posted July 21, 2006 And no CEL all this time? Did you try erasing the ECU memory and start fresh? Fuel pump, fuel filter, fuel regulator and injectors? Also check to see if the timing belt jumped a teeth, and the hydraulic tensioner? Good luck and keep us posted. Pye Quote Link to comment Share on other sites More sharing options...
nipper Posted July 21, 2006 Share Posted July 21, 2006 you may have to rent a code reader. Run the reader in real time mode and when the car starts acting up freeze the window and read the data. You can either decipher it yourself or share it here with us. How is your o2 sensor? nipper Quote Link to comment Share on other sites More sharing options...
cls1000 Posted July 21, 2006 Author Share Posted July 21, 2006 i have a code scanner, and nothing has ever showed up on it. weird. it did have a belt put on it at 60k, and i thought about pulling it off and checking it (the subaru dealer did it, so i would assume it's right) but you never know. i've replaced belts on these before so i know how to do it...but being the problem isn't constant, it would lead me away from that line of thinking....i had a belt jump a tooth on my sho and it wouldn't even start!! anyway, i'm thinking about replacing the front o2 sensor now after reading some other posts, and also that my mileage has gone down, with over 100k, i'm sure it prob. needs one anyway..i've been a member over at e46fanatics.com for years, first time to the subaru forums, seems to be a knowledgeable group of people, i like it!!! Quote Link to comment Share on other sites More sharing options...
Manarius Posted July 22, 2006 Share Posted July 22, 2006 You're having the exact same problem I am with my car. Mine idles like crap and hesitates like mad to the point where it's not driveable at this point in time. I have pretty much the same engine as you, only with a different ECU, so as soon as I get my problem nailed down, I'll post here so maybe you can try that fix. Quote Link to comment Share on other sites More sharing options...
nipper Posted July 22, 2006 Share Posted July 22, 2006 i have a code scanner, and nothing has ever showed up on it. weird. it did have a belt put on it at 60k, and i thought about pulling it off and checking it (the subaru dealer did it, so i would assume it's right) but you never know. i've replaced belts on these before so i know how to do it...but being the problem isn't constant, it would lead me away from that line of thinking....i had a belt jump a tooth on my sho and it wouldn't even start!! anyway, i'm thinking about replacing the front o2 sensor now after reading some other posts, and also that my mileage has gone down, with over 100k, i'm sure it prob. needs one anyway..i've been a member over at e46fanatics.com for years, first time to the subaru forums, seems to be a knowledgeable group of people, i like it!!! use your scanner in real time. Freeze the window when the car stalls then go read the data. See if there are nay out of spec or non existant readings. nipper Quote Link to comment Share on other sites More sharing options...
Kilroy Posted July 22, 2006 Share Posted July 22, 2006 Sounds like what my car was doing, putting in another MAF from the junkyard seemed to fix the problem. The original MAF that was in there was spotlessly clean and none of the wires were broken, this sensor is too damned picky! Quote Link to comment Share on other sites More sharing options...
Manarius Posted July 22, 2006 Share Posted July 22, 2006 Sounds like what my car was doing, putting in another MAF from the junkyard seemed to fix the problem. The original MAF that was in there was spotlessly clean and none of the wires were broken, this sensor is too damned picky! When it comes to replacing sensors, that's the only one I'm down to. My ECU threw codes for the Knock and MAF, but the Knock sensor doesn't cause this kind of issue. I'm having an MAF shipped to me ASAP. Quote Link to comment Share on other sites More sharing options...
ferret Posted July 22, 2006 Share Posted July 22, 2006 When it comes to replacing sensors, that's the only one I'm down to. My ECU threw codes for the Knock and MAF, but the Knock sensor doesn't cause this kind of issue. I'm having an MAF shipped to me ASAP. Oh we would like to believe this, but the output of the knock sensor is used by the ECU to control timing. If you have one that's a little too sensitive, or an older engine with a few more metallic sounds than it had when it was new, the sensor reads these as 'knock' and the ECU does it's job of retarding the timing. On other forums this has caused hesitation and drivability problems without ever setting a code. Just more food for thought.......P.S......passed thru Dillsburg many times since I grew up in Pa......on the way to Gettysburg or better yet Hanover...to get UTZ cheap at their company store. Quote Link to comment Share on other sites More sharing options...
Manarius Posted July 22, 2006 Share Posted July 22, 2006 Well, I may just call Autozone today to see if they have the part so I can go get it. I know my knock sensor has a big giant crack in it. Yeah, Dillsburg is one of those towns between "somewhere" and Gettysburg. It's a nice place though . I went to the Utz factory a long long time ago on a tour, it was nice. Quote Link to comment Share on other sites More sharing options...
cls1000 Posted July 22, 2006 Author Share Posted July 22, 2006 Well, I may just call Autozone today to see if they have the part so I can go get it. I know my knock sensor has a big giant crack in it. Yeah, Dillsburg is one of those towns between "somewhere" and Gettysburg. It's a nice place though . I went to the Utz factory a long long time ago on a tour, it was nice. i replacd my knock sensor with an oem piece from the local sub. dealer....cost me around $80..... and speaking of this, has anyone successfully used the desensitizing method on the knock sensor to cure hesitation??? Quote Link to comment Share on other sites More sharing options...
Setright Posted July 22, 2006 Share Posted July 22, 2006 NO! Don't do it. The ignition timing may be advanced so far as to damage your pistons/rods/bearings. Quote Link to comment Share on other sites More sharing options...
Manarius Posted July 22, 2006 Share Posted July 22, 2006 Replacing the knock sensor didn't get rid of it. I'm slowly running out of sensors to change :-( Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 22, 2006 Share Posted July 22, 2006 so far i replaced the fuel pump, fuel filter, plugs, wires, oem tps sensor, oem knock sensor, air filter, and some other misc. things. the throttle body i took off and cleaned it, you could eat from the inside of that thing...the mass air flow meter is nice and clean, and i'm running out of things to check. I'll repeat what I said in my response to your original post--consider replacing the Engine Coolant Temperature Sensor if you haven't already. You didn't mention how many miles you have on your '98, but Temp Sensors can weaken/fail/whatever in time. This confuses the ECU and it will often stay in open loop, which might explain some of your symptoms. They are not terribly expensive (under $30 IIRC) and not too difficult to replace. Made a BIG difference in my '95 Legacy a year or so ago. Quote Link to comment Share on other sites More sharing options...
cls1000 Posted July 22, 2006 Author Share Posted July 22, 2006 NO! Don't do it. The ignition timing may be advanced so far as to damage your pistons/rods/bearings. my ign. timing is 20 according to the scan tool. desensitizing the knock sensor won't advance my ign. timing. does anyone know what timing is supposed to be?? Quote Link to comment Share on other sites More sharing options...
cls1000 Posted July 22, 2006 Author Share Posted July 22, 2006 I'll repeat what I said in my response to your original post--consider replacing the Engine Coolant Temperature Sensor if you haven't already. You didn't mention how many miles you have on your '98, but Temp Sensors can weaken/fail/whatever in time. This confuses the ECU and it will often stay in open loop, which might explain some of your symptoms. They are not terribly expensive (under $30 IIRC) and not too difficult to replace. Made a BIG difference in my '95 Legacy a year or so ago. yeah i said it has like 123k on it...and i am going to replace that sensor after reading your post, the part is cheap enough anyway, i just haven't picked one up yet figure it's a good time to put in some fresh anti-freeze as well..... Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 22, 2006 Share Posted July 22, 2006 yeah i said it has like 123k on it... Ooops, sorry! Anyway, hope it helps. Good luck. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted July 22, 2006 Share Posted July 22, 2006 Not sure if this helps a whole lot, but speaking of engine coolant temp sensor, I had a CEL/MIL indication a few months ago for it in my '96 Legacy, I didn't really notice much difference in performance after I replaced it. I had a similar rought idle/acceleration issue in a '91 Escort I had years ago, and it turned out to be the aftermarket PCV valve I installed a few weeks before was bad, the dealer replaced it and it ran fine after that, but I think you already replaced the PCV valve you said, plus Subaru and Ford PCV systems might be different. Louis :-) Quote Link to comment Share on other sites More sharing options...
cls1000 Posted July 24, 2006 Author Share Posted July 24, 2006 well here's an update. ever since i cleaned out the iac and readjusted the tps, the car has been improving daily (even though the iac didn't appear very dirty) so i'm going to remove it once more and let it soak for a day or two (vs. just spraying it out) to make sure it's 100% clean and put in a new O2 sensor and see how that fairs.....i drove it yesterday to the steeler superbowl concert at heinz field, about 100 miles round trip or so, and it drove great.... Quote Link to comment Share on other sites More sharing options...
Subaru_for_LIfe Posted July 24, 2006 Share Posted July 24, 2006 Congrats! I'm glad you've got it all sorted out Quote Link to comment Share on other sites More sharing options...
Manarius Posted July 25, 2006 Share Posted July 25, 2006 Replacing the MAF did my car right up. Hard to believe a little thing like that could make a car drive so badly. Quote Link to comment Share on other sites More sharing options...
cls1000 Posted July 27, 2006 Author Share Posted July 27, 2006 well, monday, after leaving the IAC soak in some sea foam over night...i put it back in, new O2 sensor, recalibrated the TPS (got it right at .50v) and the car has drvien perfectly for the first time in about 2 years....seems to me after all this time maybe it was just a carbon build up in the IAC after all...needless to say i'm so freaking happy you could not believe it!! i don't even have an desire to drive my 01 3 series now that my wagon is running good!! thanks guys for all your help, i just hope now my mileage goes back up....i still would knock down 28 on the high way, but the city mileage had dropped from 20ish to 15ish....so we will see....but ahhh screw the mileage, i can pull out in traffic now w/ out the worry of getting t- boned!!!! Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 28, 2006 Share Posted July 28, 2006 . . . the car has drvien perfectly for the first time in about 2 years.... Ain't it a great feeling?!! Good for you for sticking with it. Quote Link to comment Share on other sites More sharing options...
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