ehsnils Posted December 23, 2018 Share Posted December 23, 2018 Or some fool plugged a hose with a rag and then forgot to remove it when they put it together. Has happened before. Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted December 23, 2018 Author Share Posted December 23, 2018 this car has been serviced by one dealer since it was new. I got the car from that dealer with 19K on it and it has had this problem for the last 38K miles so I am assuming that the leaser of the car noticed it and turned it back in.... anyways waiting for the temps to dip back down into cold range (low teens) Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted December 26, 2018 Author Share Posted December 26, 2018 OK found this on the Subaru outback forums and this does explain a bit, so I am going to press Subaru to change out the t-stat one more time and verify that the passages are clean. With the FB, the coolant flow through the heater circuit is reduced when the thermostat is closed, and only opens when the thermostat opens. This is effected by a two-sided thermostat. (See attached picture.) The amount of heat available for heating the cabin is reduced until the engine is fully warmed up. But, because engine heat is not being lost to the cabin, the engine will tend to warm up faster than the earlier models. The apparent absence of cabin heater output in the early stages after cold start up isn't because the engine is slow to warm up. link to post https://www.subaruoutback.org/forums/465655-post15.html Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted December 31, 2018 Author Share Posted December 31, 2018 This morning 12 mins after starting car, half way to work, sitting at the stop light in gear.. .and YES that is STFT percentage of 27.34 Link to comment Share on other sites More sharing options...
nads Posted January 1, 2019 Share Posted January 1, 2019 I can't find any temperature compensation tables but the 35*F air might be adding some. How was it running/driving? Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 1, 2019 Author Share Posted January 1, 2019 drives like crap until it gets fully warmed up Link to comment Share on other sites More sharing options...
08SpecB_DE Posted January 2, 2019 Share Posted January 2, 2019 Have you smoke tested the motor? What are your fuel trims cruising 50mph? What is your maf reading when the stft is that high? Have you tried unplugging the maf to see if the issue smooths out or if the car shuts off? Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 2, 2019 Author Share Posted January 2, 2019 see attached files, the 2 lower left are at 60... Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 2, 2019 Author Share Posted January 2, 2019 torque logtorque 01-02-19.csv Link to comment Share on other sites More sharing options...
08SpecB_DE Posted January 3, 2019 Share Posted January 3, 2019 First thing I'd do is smoke the motor. Even around operating temp, your stft is way lean. Another thing to try is unplug the maf and see if the numbers drop. +/- 10 is acceptable for fuel trims but +/- 5 is ideal. Unplugging the maf should kill the car, if it doesn't, there's a good chance it's bad. Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 3, 2019 Author Share Posted January 3, 2019 MAF was replaced 8 months ago along with Front o2.... Link to comment Share on other sites More sharing options...
08SpecB_DE Posted January 4, 2019 Share Posted January 4, 2019 Time for a date with a smoke machine. New doesn't mean it's good but it was just a quick test you could do in 2 seconds to rule it out. Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 4, 2019 Author Share Posted January 4, 2019 when I replaced the MAF it corrected the issue of the car smelling like raw fuel and readings at warm idle returned to normal... instead of jumping wildly all over the place. I have asked Subaru to Smoke test the engine when cold... Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 4, 2019 Author Share Posted January 4, 2019 *Update* Subaru Tech has confirmed extremely long warm up time. Smoke test to be done when engine is super cold Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 7, 2019 Author Share Posted January 7, 2019 new t-stat installed and car is now acting as expected. no more crazy long heat up times. Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 8, 2019 Author Share Posted January 8, 2019 Confirmed fix, drove to work today and MPG remained at a solid 30 on the display, no more 20-22mpg and the heat output is good. car comes down off of high idle faster car does not smell too rich car does not hesitate car gives good heat much faster so I would say all is good Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 9, 2019 Author Share Posted January 9, 2019 maybe I spoke too soon? car tossed out a P0171 this morning, heat is awesome and car is still getting good mpg. STFT at idle is a whopping 35% when fully warmed up. So it looks like the stuck open tstat was masking the issues that I was having with P0717 last year about this time. Link to comment Share on other sites More sharing options...
dgoodhue Posted January 9, 2019 Share Posted January 9, 2019 Reset the code and see if it comes back. The ECM might be adjusting the long term fuel trim from a bad thermostat and a large readjustment may be tripping a code. I had a bad individual coil pack on a Nissan and the new coil pack trip an O2 sensor fueling code. I reset it and it never came back in the 50k miles I owned it after that. Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 9, 2019 Author Share Posted January 9, 2019 Not touching it. This was the same code I had last year in the same conditions (COLD and the STFT is pegged at 35% even warm sitting at idle for extended times... Link to comment Share on other sites More sharing options...
08SpecB_DE Posted January 11, 2019 Share Posted January 11, 2019 Did they ever do the smoke test? Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 11, 2019 Author Share Posted January 11, 2019 yes, no issue with integrity but it was already warm when (Jan thaw here temps in the mid 40's). I picked the car up Monday, drove it home (50 miles) got 32.5mpg according to the display (it is within .3mpg vs calculated after I did the adjustment. Last time I verified was on a road trip 2 months ago). Heat output is fantastic now- enough to roast you out so I was very pleased and thought we were done. Drove it to work Tuesday morning no issues MPG remained good coming down to 31mpg heat still works roasting you out by them time I am at work (10 mile trip each way) Drive home, no change, MPG remains at 31 mpg... Wednesday morning shows up.... start car wait 1 min back out of detached garage.... Get out to close door, hrm smells a little rich.. get in and notice that the STFT is pegged at 35+%... uh oh... drive car to work. come to stop light in town coast down to stop, car immediately stumbles as STFT goes from 0 to 35+% (assuming that is when the injectors turned on to run the engine after fuel cut when throttle was lifted to coast down) .5 miles later get the Subaru blinking Christmas tree and code P0171 is set, car runs rough, gas mileage begins to tank. By the time I get home. Display is reading 25.2. Start car to go to work Thursday and same thing as Wednesday but fuel consumption is now down to 24.6. After work, drive car back to dealer and MPG makes it's way back up to 25.8mpg o over 40 mile drive... EDIT: yes I know the MPG meter is not the best thing to use but it is all I have to work with and it does give an indication of relative performance MPG wise ie you can use it to get an idea of what is going on. EEDIT 2: Just to recap: the following have been replaced 1. MAF 2. front o2 3. New air filter as of August 4. air purged multiple times. Talked to Subaru Dealer and they said the car was up to operating temp in a timely manner but the t-stat was not opening as it should causing the significant delay in heat output. This is reason #1 why you never trust sensor readings. the coolant temp sensor is located where it reads coolant temp in the engine and is before the t-stat. Link to comment Share on other sites More sharing options...
nads Posted January 11, 2019 Share Posted January 11, 2019 I do know o2 sensors can get loaded with soot if they have been subjected too excessive rich conditions. A can of air cleans them well. There is something tripping a lean condition. Can you monitor AFR? What is the warm idle vacuum in park? Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 18, 2019 Author Share Posted January 18, 2019 Still no car... they want to keep it for another week state that they canot resolve P0171 code... da fug? Link to comment Share on other sites More sharing options...
08SpecB_DE Posted January 20, 2019 Share Posted January 20, 2019 Freeze frame data of when the code set would be beneficial. Maybe the ect sensor is lagging and tricking the computer into thinking the car is still cold or an 02 sensor is dropping out. Link to comment Share on other sites More sharing options...
YeuEmMaiMai Posted January 21, 2019 Author Share Posted January 21, 2019 I am no longer in possession of the car... been with Subaru for the last two weeks Link to comment Share on other sites More sharing options...
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