starfox5194 Posted January 3, 2012 Share Posted January 3, 2012 I've got a 95 Legacy outback wagon with a 2.2L 5MT. Car has 124K on it. I just did a tune up. Original MPG at about 118K miles on the car 17-19 (varied driving habits city driving) MPG before oil change 17-18 no matter how hard I tried(fuel quality lowered in CT and Lucas Oil leak protection additive city driving) Changed engine oil to fully synthetic Valvoline Max Life with seal conditioners. Changed transmission and rear differential fluid put in redline MT-90 Fully synthetic. Now at 124K Got about 18.5MPG in mixed driving. I was pretty frustrated. Just replaced PCV valve and still have to drive a bit to see if that helped. Old one was clogged with oil. I just had my timing belt done at 118K So it's NOT being taken apart to fix oil seals. I'm thinking about changing my O2 sensors. All of them. I think there are 2 or 3? I don't think they were ever changed. I have a K&N air filter which looks clean probably last changed at 50K. Looks brand new though. My tires are topped off with air biweekly. They lose air pretty fast. What else can I do to my car mechanically that will increase gas mileage? I'm expecting miracles from my O2 sensors. Are my standards set too high? I'd like to get this thing to at least 21 or 22 mpg city. Quote Link to comment Share on other sites More sharing options...
jarl Posted January 3, 2012 Share Posted January 3, 2012 Assuming you don't have any CEL on: - Make 100% sure brakes are not dragging. Check the wheel temperatures after driving for a while - Knock sensor may reduce MPG without much indication, as do the upstream O2 sensor - Visit Ecomodders Quote Link to comment Share on other sites More sharing options...
ketkuFIN Posted January 3, 2012 Share Posted January 3, 2012 Reduce weight and drag by removing all unnecessary things. Replace spare wheel with fix-a-flat or similar turn off all electronics you dont need Dont drive with your windows open Keep gas tank almost empty i think thw biggest impact on fuel economy would be how you you drive and by changing that, there can sometimes be a HUGE difference Quote Link to comment Share on other sites More sharing options...
Caboobaroo Posted January 3, 2012 Share Posted January 3, 2012 What was done during the tune up, as far as what was replaced. What parts were used to replace the parts that were replaced? Quote Link to comment Share on other sites More sharing options...
starfox5194 Posted January 3, 2012 Author Share Posted January 3, 2012 I checked out ecomodders. Seemed cool but not what I'm looking for. I'm not looking for extreme MPG solutions. I'm trying to find out why my car is not getting the same MPG as people on this forum with a similar car. Checking to see if my brakes are dragging is a very good idea. I will try that when I get some time this week or tomorrow. If I do discover that my brakes are warm/hot after driving a few miles without braking, how would I go about fixing that? My brakes are old and probably need to be fixed. I never thought they would affect my MPG. I was looking at replacing the knock sensor too, but i wasn't sure if it really had a lot of MPG impact. Caboobaroo. Sorry I didn't mean to mislead you about the tune up. By tune up I meant that I tuned up the car myself by changing the fluids and replacing the PCV valve. I've tested my MPG with varied driving habits. It doesn't seem to make as much of a difference as I would hope. The most MPG I have been able to squeeze out of my car CITY DRIVING was 19 MPG. By coasting as much as possible and accelerating as efficiently as possible. I probably hurt my brakes a little. Quote Link to comment Share on other sites More sharing options...
jarl Posted January 3, 2012 Share Posted January 3, 2012 (edited) I checked out ecomodders. Seemed cool but not what I'm looking for.. . . If I do discover that my brakes are warm/hot after driving a few miles without braking, how would I go about fixing that? Ecomodders suggestions are good, and not just for "extreme" people. The "65 suggestions" are really good (at least in my humble opinion ): http://ecomodder.com/forum/fuel-economy-mpg-modifications.php Of course, the first thing to do is making sure the car is working correctly As for the brakes, you'll want to make sure the pins are in good condition and the pads can move freely. In my car the pads were absolutely stuck, with one of the two pads on one side dragging and the other one not touching the disc *ever* There are some threads here about cleaning/overhauling the brakes. Edit: Sorry for the late edit, but this may be relevant: http://ecomodder.com/forum/showthread.php/list-common-mechanical-problems-hurt-fuel-economy-5322.html Edited January 3, 2012 by jarl Quote Link to comment Share on other sites More sharing options...
Olnick Posted January 3, 2012 Share Posted January 3, 2012 Tuneup usually includes new plugs (use NGKs) and plug wires (OEM!). Also new air and fuel filters--can't speak to the K&N filter, most of us believe in the stock air box and paper filters. Inspect your knock sensor and replace it if it's cracked. New front O2 sensor might help. Check the hoses leading to the PCV to make sure they're not gunked up. If your brakes are hanging up or dragging it can wreck your mpg. Check the brake pads for uneven wear and make sure the slide pins are clean, smooth and well greased (with brake caliper grease only.) That should help your car's efficiency. Quote Link to comment Share on other sites More sharing options...
Caboobaroo Posted January 3, 2012 Share Posted January 3, 2012 Tuneup usually includes new plugs (use NGKs) and plug wires (OEM!). Also new air and fuel filters--can't speak to the K&N filter, most of us believe in the stock air box and paper filters. Inspect your knock sensor and replace it if it's cracked. New front O2 sensor might help. Check the hoses leading to the PCV to make sure they're not gunked up. If your brakes are hanging up or dragging it can wreck your mpg. Check the brake pads for uneven wear and make sure the slide pins are clean, smooth and well greased (with brake caliper grease only.) That should help your car's efficiency. This!!!! Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 3, 2012 Share Posted January 3, 2012 That K&N may be hurting more than it helps. The oil in the filter can coat the MAF sensor element and cause it to read incorrectly. Put a paper filter in it and spray the MAF sensor with MAF sensor cleaner. Oxygen sensors can make a huge difference. The front sensor is used to make changed to the fuel mixture, the rear sensor is a waste of money to change unless you get a code for it. Vacuum leaks will make a difference as well. 17 year old rubber vacuum hoses are hard as a rock and brittle. Quote Link to comment Share on other sites More sharing options...
bstone Posted January 3, 2012 Share Posted January 3, 2012 Seafoam into the brake booster. Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted January 3, 2012 Share Posted January 3, 2012 Another thing to check is your coolant temperature sensor. Not the one with the single female spade, but the one with the brown plug. They're located on the passenger side of the engine underneath the intake mani. Primary o2 sensor in the y-pipe is a culprit, as are clogged cats. Quote Link to comment Share on other sites More sharing options...
starfox5194 Posted January 3, 2012 Author Share Posted January 3, 2012 I had a mechanic check my vacuum hoses at 118K miles when I first got the car and he said they all looked fine. I checked my brakes to see if they were rubbing twice today. First drive was about 3 miles. I didn't use the brakes at all and had the car roll to a stop. Put the car into reverse and shut off the engine. Left the E-Brake disengaged. Touched the metal discs? Plates? And they were just as cold as the rims/the rest of the car on this cold winter day. I took the car out again this time driving about 8 miles ranging all the way up to fifth gear. I over-revved the engine a few times and did all I could to get those brakes hot without actually stepping on the petal or pulling the E-brake. I touched the shoes and discs (forgot about the shoes the first time) and felt no heat whatsoever. I will talk to my uncle who knows about brakes this weekend and ask him what he thinks. I didn't have time to check the mass air flow sensor, but that will be the next thing I will take a look at. I'll try to check it out tomorrow. Hopefully I will take a look at the knock sensor too. I don't know if I have an extension long enough to get at it though. I just found out about seafoam about 5 minutes ago via and I'm thinking about trying it. What does seafoaming just the brake booster do? Thanks for everyone's help. This is a great forum. Quote Link to comment Share on other sites More sharing options...
kabarakh Posted January 4, 2012 Share Posted January 4, 2012 I'm thinking about trying it. What does seafoaming just the brake booster do? The brake booster is just another vacuum line that you can put seafoam in. Many people use the PCV line instead. As long as it "feeds all 4 cylinders safely" as it states on the bottle then I believe that for all intents and purposes any vacuum line may be used. I've used it in my PCV line without any issues, and I know several people who prefer using the brake booster line. Doesn't seem to make much difference. Quote Link to comment Share on other sites More sharing options...
starfox5194 Posted January 4, 2012 Author Share Posted January 4, 2012 And I don't have to change any fluids after? It just does its cleaning process and leaves when it's all gone? Quote Link to comment Share on other sites More sharing options...
kabarakh Posted January 4, 2012 Share Posted January 4, 2012 When it's put into the vacuum lines it will all burn up, same when it's put into your gas. Most who I've talked to about it recommend only adding it to your oil if you have an oil change coming up in a few hundred miles, it cleans your oil system just as thoroughly, but (unless your burning oil) will not leave the system until you change the oil. Unless the oil is changed after it's added everything it scrubs out of the system will just hang out in your oil pan and keep recirculating. On another note, when you add it to your vacuum lines make sure you do it outside, if it's never been done before the car will completely disappear in the cloud of smoke that it produces. Quote Link to comment Share on other sites More sharing options...
ketkuFIN Posted January 5, 2012 Share Posted January 5, 2012 What is this seafoam? I'we heard so much about it and wanted to try it but i can't find it anywhere in finland. is it possible to order from internet and is it possible to get it shipped to finland? Sounds almost magical stuff Quote Link to comment Share on other sites More sharing options...
naru Posted January 5, 2012 Share Posted January 5, 2012 What is this seafoam? I'we heard so much about it and wanted to try it but i can't find it anywhere in finland. is it possible to order from internet and is it possible to get it shipped to finland? Sounds almost magical stuff http://hildstrom.com/projects/seafoam/index.html Quote Link to comment Share on other sites More sharing options...
starfox5194 Posted January 5, 2012 Author Share Posted January 5, 2012 (edited) Put 1/3 of a can of seafoam into the PCV today and another 1/3 in the gas tank. Waited 15 minutes. Revved heavily. I could barely see any smoke. There was a decent amount of smoke while I was putting the seafoam directly into the PCV, but after I restarted the car there wasn't really any. I had a second person keeping the rpm at around 1.5K while filling the pcv because otherwise the engine would stall. The car seems to run a little better, but it could definitely just be my mind playing tricks on me. There is definitely a lot of oil running through my PCV tube and the brand new valve is filled with oil once again. I did a quick google search and I read this is normal. I just filled my tank today. Put in nine gallons of gas. did some quick math. 16.8999 MPG. OUCH. Went to the auto parts store. A new knock sensor is 50$. I couldn't dare ask how much an O2 sensor was. I have a hunch that I may have a blown head gasket? Remember, totally just a hunch. I don't know much about head gaskets at all. But what are the symptoms? I also think I am "burning oil". Not too sure what this means exactly either, but I assume that somehow the oil gets mixed with the gasoline? My muffler did have some white smoke coming out of the tailpipe which *might* have stopped after using the seafoam.I blamed it on the cold weather though. I live in connecticut and mostly drive to school in the morning so it's dark and cold. I put in a remote started so the car has plenty of time to warm up. Any ideas on where I should go from here? Edited January 5, 2012 by starfox5194 Quote Link to comment Share on other sites More sharing options...
jarl Posted January 5, 2012 Share Posted January 5, 2012 (edited) Time to calm down. You sound like an hypochondriac I would start by cleaning the MAF like John said. Personally I would remove the K&N and revert to OEM filters. Make sure you used the right spark plugs (you changed those, right?) and try to diagnose the whole thing without throwing parts at the car hoping to eventually hit the MPG jackpot. Make sure you check the vacuum produced by the car. "Hoses look good" means just that, but you don't know if there's a disconnected hose somewhere. Can you post a picture of your engine bay? I'm kind of curious... I wonder if the previous owner did something else beyond installing the K&N... BTW: EJ22 engines seem to be very robust, and judging by their reputation I don't think you have a blown head gasket. Also, if you car was burning oil (which means exactly that... oil getting to the combustion chambers and being burn along the air/gas mix) the smoke would be bluish. Edited January 5, 2012 by jarl typo Quote Link to comment Share on other sites More sharing options...
starfox5194 Posted January 5, 2012 Author Share Posted January 5, 2012 (edited) I'll post photos tomorrow. It's too dark outside now. Any requests of certain spots to photograph? Thanks for the reply though. I totally forgot about the MAF sensor. Anyone know how much a MAF sensor costs/good place to get one online? I did a quick google search and as I assumed, it seems to be better to replace it rather than clean it out. But I'll buy some cleaner for it tomorrow anyways. *EDIT* Just found out a MAF sensor is 200$. No thanks. I also checked out the hoses on the car a few days ago. the only hose I saw was a tiny cut hose going through the firewall on the passenger side for A/C. I had a feeling that was how the hose was supposed to be though. Just for those curious about the history: the car was originally owned by my uncle in maryland who is very good with mechanics and took awesome care of the car and got all of the latest and greatest stuff for it. At about 75K it was given to my grandparents until about 118K. In that time period, the car suffered a little neglect. a crash to the right driver side door was repaired and so was the clutch. Cheap leaking tires/brakes were done too. My dad made sure the oil was always changed. I think the spark plugs may have been done too. At about 118K the timing belt and front and rear axels were done so the car would be safe for me to drive. power steering pump was replaced about a month ago and I put in two out of the four new shifter bushings. I couldn't reach the front two. The shifter is better than it was though. The car has been leaking oil for a while now. I'm not sure when it really started though. Edited January 6, 2012 by starfox5194 Quote Link to comment Share on other sites More sharing options...
Olnick Posted January 5, 2012 Share Posted January 5, 2012 I was putting the seafoam directly into the PCV, Just curious, how did you put it in? Did you use the PCV's vacuum hose to suck it into the intake manifold? Quote Link to comment Share on other sites More sharing options...
jarl Posted January 6, 2012 Share Posted January 6, 2012 Don't check the hoses but the vacuum level. That will give you a lot more information. You can borrow the vacuum gauge from autozone, or buy one at harbor freight. Quote Link to comment Share on other sites More sharing options...
starfox5194 Posted January 6, 2012 Author Share Posted January 6, 2012 Olnick, I used the vacuum hose that went from the pcv valve to some other three way connector that two other hoses went into. I couldn't put in too much at a time otherwise the engine would stall. I had to have a second person lightly pressing the gas so the engine wouldn't stall either. The seafoam was sucked up pretty fast. I will look into borrowing a vacuum gauge from auto zone. Maybe not tomorrow. Will be pretty busy all weekend. I still think my MAF might be a big culprit. And the front O2 sensor. Probably the knock sensor too. MAF cleaner is cheapest so I'm trying that first lol. Quote Link to comment Share on other sites More sharing options...
kabarakh Posted January 6, 2012 Share Posted January 6, 2012 Olnick, I used the vacuum hose that went from the pcv valve to some other three way connector that two other hoses went into. I couldn't put in too much at a time otherwise the engine would stall. I had to have a second person lightly pressing the gas so the engine wouldn't stall either. The seafoam was sucked up pretty fast. Thats because you're "supposed" to put it in so slowly that it doesn't stall out, drops at a time if you have to. The stuff contains a lot of Naptha so I think the theory is that doing it super slowly prevents damage from all the naptha burning too quickly, as well as allowing it to build up in the system. I know a few people who dribble it in until they're almost out of the stuff and then dump the rest in and allow it to kill the engine (all without revving the engine at all... one person pouring it in only) which allows some of it to remain in a liquid state while you wait the ten-fifteen minutes. I've done it both ways, quick and fast. The good news is that it cleans either way Quote Link to comment Share on other sites More sharing options...
jarl Posted January 6, 2012 Share Posted January 6, 2012 I have heard stories of people hydro-locking their engines by pouring it too fast as well Quote Link to comment Share on other sites More sharing options...
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