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Check engine and cruise control.. Help!

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Does anyone know what it means if the cruise control light blinks with the check engine light? Just before this happened, my car stuttered and stalled right after starting it up. Prior to this the car drove fine.


I checked the oil level and it was low so I added oil and gas was really low so I added gas but neither made a difference.


I'm planning on taking the car to Subaru on Monday. In the meantime I'm not going to drive it.

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How was your 710 level?
[URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard
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Brain was low so I added more brain.


Always have to check your brain levels.

[URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard
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Thanks Rizz and tailgatepro! The rest of you are discouraging a new forum member so shame on you. You were all new to this once before and probably asked dumber questions then I did so be more considerate! We are all Subaru Legacy owners on here and share a common interest. It's why we acknowledge one another on the road isn't it? It's pathetic that I got more help from the general Subaru NASIOC site then here..


And just so you know, I'm not a complete newbie to tuning.. I built an MR2 that could smoke 750GSXR's on the freeway XP then again at the time, I spent a lot of time reading and learning about them. Now, I have a family with two very young kids and a job and so I don't have the same time to do as much research as I did before and so it's easier to ask and have someone who happens to really know the issue just answer it for me.


And to people who really get on people about doing their own research, yes it's true, I could have but then again so can you about everything in life.. Do you ever ask anyone for anything? Why not do it yourself? Probably because you either don't have the time, resources or it would be more efficient to just ask someone else. For me, it's time and efficiency. Please understand this.


Anyhow back to the real issue at hand if anyone is actually willing to help!


So I had Autozone run the code for me for free which is awesome and it turns out its a P0172 which I did a ton of reading on. I'm glad to know that the check engine light plus cruise control light is a code! Lol


P0172 system too rich - bank 1


Probable cause:


High fuel pressure


Faulty FPR or injector


MAF/VAF sensor faulty


Faulty HO2S (heated oxygen sensor) bank 1




So if its "Bank 1" does that mean only one side of my Boxer motor is running rich?


If so, do I have a fuel pressure regulator for each side? If not, I can eliminate that possible cause right?


I think it's likely a injector that's faulty and stuck open since my car has 123k on it and is due for its service which I think involves replacing the injectors... Thoughts on validation of theory based on symptoms?


I've read that cleaning the MAF can help and that sometimes they just break, but again, if either were the case, wouldn't it say more than just bank 1? Is it bank 1 and bank 2 or are there more?


I've also read about checking for boost leaks and vacuum leaks, but again wouldn't that affect both sides and wouldn't the effect of a vacuum leak be running leaner?


And finally there has been a lot of talk about O2 sensors.. How much is one? I'm thinking I might just replace it just because they do seem to burn out in time and I'm planning on having my service to replace my injectors done tomorrow anyhow. But again, if the O2 were the case, would it just say bank 1?


So possible high fuel pressure.. Haha that's kind of vague but I suppose it could only be high due to a few reasons right? I have a stock fuel pump and regulator as far as I know as we'll as injectors as far as I know; not that the injectors should matter..


Here are the symptoms and circumstances of the code going off again:


Hot day, mid 70's, low on gas so stopped by the gas station by work. The gas was ridiculously high there in comparison to by home so I pumped only a little. Started the car up, it sputters/stutters and dies. I start it a second time and the same thing occurs so the third time I rev it up a little and it reluctantly goes up and stabilizes. I drive home with no issues but stop for gas by my place. I pump a full tank and start the car up and same issue. I get it started and stabilized at regular rpm and head for home. I'm out of boost and driving carefully since I'm a bit worried about the car and all of the sudden on a hill my car throws the code.


I got home, cooled down the engine and checked the oil, found it to be a little low and filled it, as well as loosening and tightening the gas cap again. Then I read up on the check engine and cruise control light combo.


Any possible scenarios or theories that I'm overlooking? Thanks everyone!

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Consider this:

1. crappy gas

2. dirty MAF

3. dirty, contaminated, old, or possibly failing O2 sensor


You're in limp mode. Don't panic. I'd look into these 3 items before I'd roll to your local stealer. Go there and and you will pay about $750 or more for DX and repair. They'll probably replace the O2 sensor as a matter of coarse.


You can buy better gas and look at the other 2 items for free. Clean up is easy... Don't spray anything or use solvent on the O2 sensor. Clear the code. Drive. If it comes back we can give more advice.

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What would you guys recommend using to clean the MAF with?


How should I go about and clean the o2 sensor? Just use a damp cloth or dry cloth? I heard of using brake cleaner to spray on hoses to check for leaks but that stuff is flammable so is it safe to use with a turbo motor? I mean its probably unlikely that it will get hot enough to ignite without an open flame, since it'll probably evaporate first but still..

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Okay so I think I'm going to try cleaning my MAF and O2 sensor tomorrow.. Are their any tips or snags I can expect? Where is the O2 sensor located that may be the culprit for the error code? I've never been under my car yet so I'm not sure where anything really is. Can I access it without taking a bunch of stuff off?
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I did a bit of research on the matter and some say to use brake cleaner on the MAF while others say to use intake or carb cleaner.. Which is better and why?


Hmm I think I'll just replace my air filter tomorrow as well while I'm at it.

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Okay so I bought the stuff and cleaned my MAF sensor and disconnected the negative terminal to reset the code.


Currently I don't have an error code being thrown but when I watch my mpg calculator it's still reading that I'm getting really bad mileage per gallon; a little better than before I cleaned the MAF but still way worse than before I threw the code.


Based on that, I suspect the code will return after the car collects enough data.


If I happened to know another legacy GT owner I'd try swapping the MAF for a known good working one to trouble shoot whether its the reason for my error code, but I don't.


Anyone in Seattle area willing to help?


I may just take it to Subaru and have them check my O2 sensor and check my injectors since I want to get an oil change anyhow.. But at $108 per hour it's a bit ridiculous!

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I did call Subaru and speak to an advisor and inquired about the term bank 1 and as I suspected, there is a bank 2 and they refer to sides of the motor.


Being as that's true, I think it may be safe to assume that it has to be related to something that is independent of the other side. Thereby eliminating a faulty fuel pressure regulator, MAF/VAF and the Heated Oxygen Sensor (HO2S). This leaves a faulty injector as the biggest probable cause does it not?


Is there a HO2S on both sides of the motor?

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No worries, I'll be blunt in return. Of course I don't know much about this car. I just bought it. How much did you know after only owning it for a month?


And I probably know more about Toyota MR2's then you know about your car or your own parents, but thanks for your presumptuous and opinionated observation.


Alright well, back to the original topic..

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I purchased MAF cleaner and cleaned my sensor. I also disconnected the negative terminal cable to reset the code to see if it returns after driving it for a while. Over currently put about 70 miles on it and it hasn't returned yet.


The real time fuel economy gauge seems to show an improvement in MPG since I've had the error code (before cleaning the MAF), but still not as good as I recall it being.. Perhaps I'm thinking more into then I really need to.


Once I cleaned it I have also kept an eye on the average MPG as well and it's gone up from 14 MPG to almost 18 MPG average.


Before the error code I recall 17-18 if I was boosting a lot, 18-19 if I drove it normally and 19-23 if I babied it.


Perhaps the reason why my average hasn't hit as high as it normally did because of the low average being calculated in.


To figure that out, I'll just have to put more mileage on it and hope no error code returns and shows my MPG creep back up to where it used to be.


I realize this may not be too accurate of a way to track what my car is doing but hey it's working with what I have at the moment.


In any event I've ordered a precat O2 sensor and plan on installing it assuming it is general maintenance, however at this point it's the probably cause of my running rich.


I called a dealer to make sure the part number I was going to order was correct and they of course said without me providing my VIN number they can't give me an answer with 100% certainty. And then said that the part number I provided is one of two precat O2 sensors listed for that year and model. There is one for a EJ25 and the part number is 22641AA280 and one for a EJ255 and the part number is 22641AA32A. I asked what's the difference between a EJ25 and EJ255 and the parts department guy said he wasn't sure so I'd need my VIN to take the guess work out of it.


So I called another dealer and asked the difference and was told the EJ25 is a NA motor and the EJ255 is a turbo motor. Is that correct?


And since I'd had my car serviced there before I suspected that they had my VIN on file so I asked the parts department to look up my precat O2 sensor part number based on my VIN and the part number came up as 22641AA32A.


So for sure, my 2005 Legacy 2.5GT wagon in manual transmission has that O2 sensor part number. And if what the dealer is saying is correct and true, then all the NA models with EJ25 motors would use the 280 part number, while the turbo motors would use the 32A part number.


I hope this helps someone else out in the future!


Oh, one more side note is that I used to have a slight bucking that I would feel when cruising between 2500-3500 RPM which seems to have gone away or gotten so mild I hardly notice it.


I had previously asked about that and people said it was due to the stock tune and that the stock tune sucks, so getting an AP and tuning it would make it better.


I'm starting to think that it was actually just a dirty MAF so if anyone else is having that issue, I'd suggest getting the MAF cleaner for like $8, and take five minutes (literally 5 minutes) to pull off the sensor from the top of the intake box and spray it off with the cleaner and let it dry before reinstalling it.

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Tell us again how much you know about MR2's.
[URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard
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