deuce Posted April 5, 2005 Share Posted April 5, 2005 The title pretty much says it. I have an 89 GL wagon that within the last month has been losing power, and gas mileage. Where should I look first? Quote Link to comment Share on other sites More sharing options...
85Sub4WD Posted April 5, 2005 Share Posted April 5, 2005 O2 sensor plugs, wires, distributor cap, rotor fuel filter Quote Link to comment Share on other sites More sharing options...
roxtar Posted April 5, 2005 Share Posted April 5, 2005 yup, general tune-up and O2 sensor is the best place to start Quote Link to comment Share on other sites More sharing options...
MorganM Posted April 5, 2005 Share Posted April 5, 2005 Feel free to post your results and ask more questions if it continutes after a tune up and Oxygen sensor. Quote Link to comment Share on other sites More sharing options...
Sweet82 Posted April 5, 2005 Share Posted April 5, 2005 I have never replaced my 02 sensor What do they look like? Is that the thing on the side of the air cleaner? I have no problem asking stupid questions :-p Quote Link to comment Share on other sites More sharing options...
deuce Posted April 5, 2005 Author Share Posted April 5, 2005 Cap, rotor, and plugs relatively new, not sure the age on the wires. I was going to try a fuel filter, and check the cat. I will also try to see if there is a vacuum leak. Quote Link to comment Share on other sites More sharing options...
MorganM Posted April 6, 2005 Share Posted April 6, 2005 I have never replaced my 02 sensor What do they look like? Is that the thing on the side of the air cleaner? I have no problem asking stupid questions :-p These only come equiped on fuel injected or feed back carb engines. It's a sensor that screws into your catalytic converter. On the old Subarus it shoud just have a single wire down to it; my Legacy was a 3 wire one (signal, preheater, ground). It's about the size of a 16mm deep socket. Your Forester has two I think; one before and one after the cat. Quote Link to comment Share on other sites More sharing options...
deuce Posted April 11, 2005 Author Share Posted April 11, 2005 Okay, I used Seafoam, changed the fuel filter, will probably change oil/filter this weekend, plugs, cap/rotor are relatively new, wires are fine. What else? o2 sensor, I don't hear anything rattling in the cat, and I feel a pulse at the tail pipe with the engine idling. My top speed on level ground is 64, when I used to be able to do 75, and mileage went from 26-29 down to 21. Without spending a fortune ( the car is not worth it), what else can I do or look for. Also no noticable vacuum leaks. Timing is at 18 as well. Quote Link to comment Share on other sites More sharing options...
MorganM Posted April 12, 2005 Share Posted April 12, 2005 O2 sensor could be a culprit on the milage. Also running 18deg BTDC is going to kill your acceleration. Did you turn it down for a reason? Might want to address that reason. Backpressure test at an exhuast shop can tell you if the cat is clogged. Real cheap and easy way to fix these cats if they get clogged Quote Link to comment Share on other sites More sharing options...
deuce Posted April 12, 2005 Author Share Posted April 12, 2005 Sorry, mistyped, should be 20deg on timing not 18. Quote Link to comment Share on other sites More sharing options...
MorganM Posted April 12, 2005 Share Posted April 12, 2005 Sorry, mistyped, should be 20deg on timing not 18. No problem. Swap in a new O2 sensor and see how she rides. Just a simple one wire sensor; should be cheap. Easy enough to replace also. Worst case you'll have to drop the Y pipe down off the engine to get access to it. I use a special O2 sesnor socket but a big wrench works too Quote Link to comment Share on other sites More sharing options...
deuce Posted April 13, 2005 Author Share Posted April 13, 2005 Okay, this car is our daily beater, I mean commuter. SO the only real time to work on it is on weekends. Anyway, today after driving a few miles, the check engine light came on for 25 or so miles, then went out. Can I retrieve the code if the light went out? What harness or harnesses get connected by the firewall? How can I get the code? This may help figure out the real problem. I plan on replacing the o2 sensor this weekend, but if I can retrieve the code, that may help diagnose the problem. BUT, like I said the check engine light went out after around 25 miles. The Chilton manual (came with the car) is pretty much garbage. I've never been a real fan of them for any vehicle. Quote Link to comment Share on other sites More sharing options...
MorganM Posted April 13, 2005 Share Posted April 13, 2005 This USRM article should get you squared away on retriving codes. Yes it is stored in the ECM for later retrival despite the light going off. You are correct; this just might assist in resolving your issue. http://www.ultimatesubaru.org/forum/article.php?a=44 Good luck Quote Link to comment Share on other sites More sharing options...
deuce Posted May 4, 2005 Author Share Posted May 4, 2005 A little update. It has been a few weeks since the check engine light came on and I replaced the o2 sensor. My mileage improved very slightly, from 18-19 to 20-21. Not much since it was 29 when I bought it a year ago. Power is still down, but my top speed is between 65 and 70 depending on conditions. Beside the aformentioned issues, it does not do me much good to floor the gas pedal. It seems to do slightly better backing off a bit. If I try and gas it hard, it will rev okay, but just does not seem to move very fast. I thought I read something in another post about the distributor not advancing properly (sticking). Possibility? Lifter/valve? The o2 sensor fixed the engine light, but no major improvement in performance or mileage. Quote Link to comment Share on other sites More sharing options...
85Sub4WD Posted May 4, 2005 Share Posted May 4, 2005 If I try and gas it hard, it will rev okay, but just does not seem to move very fast. I thought I read something in another post about the distributor not advancing properly (sticking). Possibility? Lifter/valve? The o2 sensor fixed the engine light, but no major improvement in performance or mileage. Me thinks vacuum leak maybe?? did you reset your computer after installing the O2 sensor (pull battery cable off and wait five minutes)?? another possibility is a valve/lifter, but usually those cause a LOT of noise as yours is an 89, you do not have a normal distribuitor, but a Crank Angle sensor - basically it uses a light and perforated wheel to tell the computer where the engine is in its cycle - no advance mechanism, the computer does that - it either works, or it doesn't (no start condition), so that is not your problem Quote Link to comment Share on other sites More sharing options...
subynut Posted May 5, 2005 Share Posted May 5, 2005 Do you hear the sound of rushing air comming from under the car when your accelerating? Since you've done a tuneup, I am almost leaning towards cloged cat or muffler. My sister's Suby did that: No power, top speed around 55, poor milage and a very noticeable hiss comming from under the car. Turned out to be clogged cats. She had the front one replaced and I gutted the mid cat. Made a world of a diference. The clogged cats was caused by too long without a tuneup. Just my 2 cents. Quote Link to comment Share on other sites More sharing options...
deuce Posted May 5, 2005 Author Share Posted May 5, 2005 Do you hear the sound of rushing air comming from under the car when your accelerating? Since you've done a tuneup, I am almost leaning towards cloged cat or muffler. My sister's Suby did that: No power, top speed around 55, poor milage and a very noticeable hiss comming from under the car. Turned out to be clogged cats. She had the front one replaced and I gutted the mid cat. Made a world of a diference. The clogged cats was caused by too long without a tuneup. Just my 2 cents. Explain the "rushing air" a little more. Is it quite noticable? Where should the sound coming from under the car (at the cat?)? My biggest problem is getting up to speed, and hills. Anything that really loads the engine. I have contemplated doing something about the cat to see if it helps. I'm running out of ideas. As for the vacuum leak idea, I've checked and have found no leaks. Unless something manifests while driving/accelerating that was not noticable while under the hood. Quote Link to comment Share on other sites More sharing options...
subynut Posted May 6, 2005 Share Posted May 6, 2005 I'll try. It's almost sounds like a hiss comming from underneath the car while your accellerating. My sister's Suby was the center cat, so it sounded like it was right under the shifter. If it was the front cat, it would sound like it's in the front by your feet. My sister's was quite loud; however, it was very clogged too. I've only been able to hear it while I'm driving. Sitting still, I can't hear it. Dat help? Quote Link to comment Share on other sites More sharing options...
deuce Posted May 10, 2005 Author Share Posted May 10, 2005 I'll try.It's almost sounds like a hiss comming from underneath the car while your accellerating. My sister's Suby was the center cat, so it sounded like it was right under the shifter. If it was the front cat, it would sound like it's in the front by your feet. My sister's was quite loud; however, it was very clogged too. I've only been able to hear it while I'm driving. Sitting still, I can't hear it. Dat help? Improved the rear cat. Is the front cat the y pipe junction? How would the pcv affect performance and mileage? With the rear cat "improved" I don't really notice a difference. Quote Link to comment Share on other sites More sharing options...
subynut Posted May 10, 2005 Share Posted May 10, 2005 Improved the rear cat. Is the front cat the y pipe junction? How would the pcv affect performance and mileage? With the rear cat "improved" I don't really notice a difference. Yes, the front cat is part of the y-pipe secton. My guess why the PCV valve can wreak havoc would be when it fails it usually fails open which causes a large vacume leak. That can cause the engine to run lean requiring more throttle to accelerate. Quote Link to comment Share on other sites More sharing options...
deuce Posted May 25, 2005 Author Share Posted May 25, 2005 For a little update...I replaced the pcv valve last weekend, and no improvement. I would almost say it is worse. Top speed struggles to get to 55-60. No uphill power at all. The speed drops like a rock. Next on my list of to check/do is to test and/or replace the coil ( how can you actually test a coil?), work on the front cat, and check the lifters. Now that temps warrant, the windows are down and I hear a little noise at part throttle, but not at full throttle (not that it makes a difference in speed). Any other ideas. Acceleration is horrible as well, not just top speed. Quote Link to comment Share on other sites More sharing options...
hooziewhatsit Posted May 25, 2005 Share Posted May 25, 2005 I think I'd check the front cat first, since it seems like everything else has been done. I had a similar problem where the honeycomb came loose and tried (unsuccessfully) to squeeze out the exhaust. NO POWER whatsoever. Find a rubber hammer and gently tap on the front cat. If you hear rattling, then parts have broken off. It shouldn't take too much work to remove the front Y pipe and see if anything falls out. You could also start the car without the exhaust to see if the throttle response is any better. Just don't do it over anything flamable good luck Quote Link to comment Share on other sites More sharing options...
deuce Posted May 26, 2005 Author Share Posted May 26, 2005 I planned to take care of the front cat this weekend. The back cat was pretty easy, the front cat could prove to be a bit more of a challenge. I'd like to remove the guts to see if it is indeed the problem. Quote Link to comment Share on other sites More sharing options...
Martin Posted May 27, 2005 Share Posted May 27, 2005 How long ago were the timing belts done? Just a thought that maybe the belts jumped a tooth, or were done wrong and are slightly off. Seems like most other things have been mentioned, but that was not. Quote Link to comment Share on other sites More sharing options...
FirstSubaruGLwagon Posted July 21, 2005 Share Posted July 21, 2005 This is a really interesting thread for me. I own a 86 GL wagon ( bought for 175. I'm poor and this my daily driver ) and I have same problem, terrible gas milage maybe around 16 mpg Replaced and plugs and air filter, no change. (wires ,cap and coil are my next investment) The car is carburated. Starts hard but then idols fine. However it tops out at about 60 mph at 3300 rpm. There is an exhaust leak at the Y pipe somewhere. (the timming belt has been serviced due to missing bolts on cover but i have no records of that.) Could all this mean a cloged or restricted Cat? OR Could this be due to a worn out 3 speed tranny? Oh, and I live on the flats of the coast so there is no big hills to test pulling power Would love to have this car when it was new I was so impressed with the little car I went to a dealer and tryed to get a new forester,,, wow , down here you have to be a rich man with exilant credit to get a new subee:mad: no dealer incentives what so ever! Quote Link to comment Share on other sites More sharing options...
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