The Subaru CEL thread

[kscoob]

2008 Subaru Impreza 2.5i Sedan stock, 113k miles

Codes: p2096, p0137

My exhaust was leaking at multiple points. After I got this fixed, the codes came back after a few days. When cleared, the CEL will illuminate after a few mins driving on the highway.

I believe that the Upstream AF sensor has a rich bias. About 5 minutes after the car warms up, it produces a consistent negative current (-0.05-0 mA). Its voltage is 2.1-2.2 V. In that time the LTFT drops from 0 to -4%.

The downstream O2 sensor provides reasonable values at first, in the 1.2-0.4 V range. However this gradually drops to 0.01-0.02 V.

The MAF sensor appears to be responsive, increasing with engine RPM.
2 g/s at idle, 10 g/s at 3000RPM.

I dont hear any vac leak whistles while the engine is being revved with the hood up.

Any ideas?

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[GoranNoSuponsaa]

2007 Impreza 2.5i Wagon, stock, 136k miles

Code: P0171 System Too Lean (Bank 1)

Taking a look at this in a bit. Either dirty MAF or serious vacuum leak. Built a DIY smoke tester out of a soldering iron and a pickle jar. Will update when I clear the code.

[Jerpster]

Here's one for you. I'm posting in this not because of a code. But the lack there of.

I'm the third owner of my 08 wrx. It has 155k miles. I bought it at 100k. Timing belt was done by PO at 90K. Paperwork to prove it was done. It was after my idler pulley exploded that I realized only belt and tensioner pulley were replaced. So I'm here about the lack of P0340 0345 codes. I have the timing belt cover off and found the issue.

Might I be the luckiest man in the world and just need to replace broken cog pulley check timing and replace timing belt water pump and compression test?

Thoughts?

[aswresm]

Any idea what to look for when trying to fix that CEL. T
Thanks in advance.

[mariposawrick]

This reply is for the general good.I expect most here are aware, but I just retaught myself this handy trick. When trying to determine my CEL reason, codes, etc., and what to fix first I noticed that my positive battery terminal was very corroded when I disconnected it. After cleaning the terminal and reconnecting it I noticed that the CEL was off. This was several weeks and over 500 miles ago. Codes are cleared, no CEL. Hope this helps others before they spend hundreds on parts they m ay not even need.

[Glass_Pizza]

I have an 08 sti hatch with no sensor activity after looking under the car I found the sensor out of the exhaust, stripped, I managed to place it back in but now the car stutters under load and runs extremely rich, any help is greatly appreciated

[Shift3r]

Originally Posted by Glass_Pizza

I have an 08 sti hatch with no sensor activity after looking under the car I found the sensor out of the exhaust, stripped, I managed to place it back in but now the car stutters under load and runs extremely rich, any help is greatly appreciated

that sensor needs replacing as they begin to misread air/fuel ratios when they’re damaged

[Phoenix Rising]

Edit: 2004 WRX
Codes: None Found

It's been awhile since I've posted, but this one makes absolutely no sense to me.


Driving down the highway (5th gear) just cruising (not romping on it) the CEL starts flashing and there's a noticeable loss of power and some shaking. Usually, that indicates a misfire, however, no codes are present. It idles rough and just straight sounds terrible.


I've cleaned the MAF, replaced plugs, and installed a new Denso oxygen sensor (upstream). After that, it will crank okay (sometimes it has trouble), idle correctly for about 15 seconds and then it goes to super rough.


My next logical step would be the TPS since I looked at live data (twice) and during one of them it read the throttle angle at 0% event though I revved to 2.5k gently (see video). The second time, I did the exact same thing and it showed me a max of 8.



Would the TPS going out cause all these issues? Could a coil pack be going out? I'll link a Google Drive folder with different things I've looked at. Just keep in mind the only changes you'll see are from idle to 2.5k rpm. Thanks in advance.


Google Drive Folder

[Scoobslife]

I have an invidia turbo back with a divorced down pipe cel is on for o2 I'm hoping after some research I can get it tuned out though please anyone knows give me advice

[DirtyWRX08]

Long story short.
Just installed all this on my 08

VF52 Turbo
Injector Dynamics X-Series Fuel Injectors Top Feed 1050cc 2002-2014 WRX
Deatschwerks DW65C Fuel Pump w/ Install Kit
Tomei Fuel Pressure Regulator Type-L
COBB LF Bypass Valve 2008-2014 WRX
COBB Short Ram SF Cold Air Intake
Grimmspeed Electronic Boost Control Solenoid
Grimmspeed Air Oil Separator
Turbo XS Front Mount Intercooler Silver
COBB Turbo Heat Shield
Perrin Turbo Inlet Hose
Invidia Cat Back Exhaust
Invidia catless downpipe
1-step colder spark plugs

After 69 days I finally was driving again. Until cylinder 1 misfires like CRAZY. talking +80 misfires just at idle.

First thing I thought was the coil pack. Well behold. And you would think that after doing spark plugs he would've said something but nah, let's just slap it back in.

[Wheat77]

I know I'm bumping an old thread here, but I've only ever lurked these forums and don't have enough replies to make my own thread yet so here we go -

Just recently bought a 2016 Impreza Sport 2.0i Premium with 124,004 miles on the clock. Car was in excellent shape aside from a worn rear bearing (already replaced, man that was easy) and a CEL with code P1449. Previous owner said he replaced the gas cap and when that didn't fix it he said "screw it, I live in a no-emissions-check county and it performs fine" so he stopped trying to remedy it.

Now I did some research beforehand and knew a few things to check, hoping I'd be able to find the issue and fix it quick. But here's the thing, I've checked everything I can think of and I'm *still* getting the code returning.

So yeah, P1449, car clears all other readiness checks but evap, no other pending codes.

Checklist so far:
-Replaced gas cap (P/O did, maybe I should test this new cap? nothing seems wrong with it)
-Pulled and checked Purge Control Solenoid Valve (per

2012 Subaru Impreza P1449 Diagnosis - YouTube

2012 Subaru Impreza P1449 Diagnosis - YouTube

) - holds closed, opens on 12v just fine, no blockages, no debris inside
-Pulled
-Pulled and checked Vapor Canister (circled in red), Emissions Check Valve (circled in blue), and Valve Canister Drain (circled in green) - this was a huge PITA and involved dropping the diff and exhaust, then a bunch of gymnastics to pop hoses of a wriggle these assemblies out from above the diff.
https://i.imgur.com/E5Yc7TZ.png

I was sure I'd find an issue with one of these or the hoses connected to them, but everything was clean, flowed correctly, opened and operated correctly, etc. etc. I cleaned them all up and put everything back together exactly how it was, reset the code again, and BAM, threw P1449 on me after a 15 minute drive.

Now, it seems to specifically throw the code after clearing all other emissions readiness checks, and during a deceleration from 60mph down to low speed/stop without hitting the brakes (following recommendations on the optimal drive cycle to clear the checks).

I'm stumped and about to take it to a tech, but I'm not sure what they can check that I haven't already.

Any ideas anyone?

[Wheat77]

Solved it! It was spiderwebs in the vapor canister drain vent. Here's what the webs looked like:
https://i.imgur.com/UCYW3Pt.jpg

And they were in the connector on the other end of this hose coming off of the evap assembly. If you trace the tube circled in red away from that white part (in the direction of the arrow), it ends at this connector clipped into the body. Gotta kinda wrestle it out and you'll probably break the clip a little, but as long as you can wedge it back in that hole you should be good. You don't have to do anything but lift the car up to get to this. If you're having the same issue I was having, check this first. It wasn't even that packed with webs but I guess it was enough to f**k it up.
https://i.imgur.com/8aO23AZ.jpeg

Good luck.

[Psythus]

Code: P0300 Random Misfire over all cylinders
Year: 2014 WRX Hatchback
Milage: 80k

I bought this car and after quarter tank of gas CEL came on. Before I bought it, initially they did repair on the exhaust, as it "held on with one bolt." That's all they said there besides rear brakes (rotors too) and wheel bearing so ... yay 2k off price of ~18k.

I brought it in, they checked plugs, changed one and the expected problem for a new coil in #4 to try and fix problem. They noticed a cut wire on engine harness, did nothing about it. They give it back, code comes back on. I bring it back obviously on them for cost. They give to an actual sub dealership, they get it in and because they're being cheap, just say to put "better gas in" (I know to use premium from my DOHC NA Stealth I had for YEARS) and I get it back with compression tests showing great (for the miles) loss at only around 3% max over all cylinders. Ignored engine harness of course for cost. It comes back on when I get it back second time.

Third time, not messing around, they DO replace for an updated engine harness. They put on a new timing belt, some gaskets, cleaned out EGR valve and intake system. They checked mass air sensor and plugs and all great. They say it's coming on during idle. I THINK that the car is accelerating normally but do not have reference for when it boosts, it DOES feel like either turbo lag or the boost is in some way limited psi but I don't have boost gauge... the car is basic inside compared to next gens, so no gauge bezzle to see if boost is dropping or nominal.

I'm left with them saying it's probably a phantom misfire...? But I have to keep clearing the code as this one is a perma code for P0300 random/multi cylinder misfire and they are just at a loss now as to the problem. They called engineers at subaru and still confused if there's something going to REALLY snowball into catastrophic failure between the 10k miles left on my 100k/2y drivetrain warranty.

I'm begging for a solution. I wish I could give the car back and grab the 2018 for same price that just popped up here in our small community, but they HAVE done a lot of work on it and it's $5,000 I can take off the price. Is there ANYTHING else I should be looking at? I'm waiting on a call back if the exhaust was checked thoroughly for clogged cat, or leak from manifold to tailpipe which I've seen can be a reason for p0300. (There is no codes for ranges of cylinders of p0301-p0304 thankfully) But I just feel someone monkey'd with the car, knew this was there, cleared the code, and traded in.. and I just hate feeling like it's sick in some way or not performing like it should because of this. The misfire comes on randomly, and can't feel anything different when it does. I'm just depressed, I wanted one so bad (I am retired firefighter, don't have A LOT of extra money for something like this to happen) and got this from a dealership for the peace of mind that I do not have. They don't want to dump any more money into this problem and I just said well I guess this is what I'm stuck with... I just don't know what else to do. I mean new fuel injection? New fuel pump? With compression loss being so good for 88k miles... is it really even an issue that could be making it under-perform?? IDK brothers and sisters please tell me if anyone else has had these continued mystery p0300's

[legrand]

Hello,
P0130: Circuit du capteur d'oxygène (Capteur 1 de la banque 1)
2008/Subaru/Impreza
Kilométrage : 100 000 km
Solution au problème : Remplacement du capteur d'oxygène.

[sloppymick]

getting a no crank after doing a tune up. the only code that comes up is P0700. I know this is a generic trans code, but curious if im getting it with no crank due to neutral safety switch issue? After the tune it started right up and idled awhile and then just quit. I was able to get it restarted a few times, but now, nothing. There is power to the car when trying to start so I dont think its anything to do with loose batt connections.

At the same time I get no crank, my OBD scanner drops out when I put key to on. It powers up normally when I plug in, and only blanks out in ON. wondering if I have an ignition switch issue and/ or neutral switch issue?

I dont see any correlation of ignition switch to trans code however.

[ephemeros]

Code: P0011/P0021
"A" Camshaft Position - Timing Over-Advanced or System
"A" Camshaft Timing Over Advanced (Bank 1)

Year/Make/Model: 09 Sti Hatch
Mileage:150k KM
Fix for problem: to be updated when found

[grubaru08]

P0457 Car dies after fueling up

Bought an ‘08 WRX that the guy said needed a gas cap. Drove home fine until the CEL came on P0011 (was just the solenoid/ocv) and P0457. Ignored it and bought a gas cap. After filling up the first time with the new gas cap the car started and stalled out, drove home while the access port told me I had an AFR of anywhere from 11.03-12.48 (very rich) this then triggered P0172 and the engine would try to cut out any time I came to a halt. Started the car in the morning and acted fine. Put half a tank in the other day car started and died… However after driving briefly it cleared up and ran fine.

Today I took the purge valve off and it seems to be operating normally.

[Fellows-23]

P0102 and P0113 maf sensor, cleared and not come.back, I did unplug to clean the maf so would that of thrown those codes?

[heraldofthesmileys]

P0341- intake camshaft position sensor...

I was on a road trip from Virginia to Alabama, car was running fine. Stopped at a Buccee's just inside the Alabama line in Auburn. I turned the car off and got some gas. When I turned the car back on it was idling wonky, checked the code and it was as stated above. I cleared the code thinking that would maybe help the issue. but now the car will not start.

I have changed the suspect cam position sensor, nothing
I have changed the crankshaft position sensor, also nothing
Everything I have done has had no effect...

It is getting fuel, has spark, is getting air, and obviously the grounds are just fine, which leads me to a timing issue hence the code and the sensors that I have replaced... It is beyond my ability to troubleshoot anymore, and I am out of Idea's... Has anyone had this issue before?

[Colossus127]

I have an 03 2.0 that I just rebuilt the engine on from the block all the way up. Car runs great but has been throwing a P1086, TGV #2 low circuit code since I rebuilt it.

I did take the sensors off when I rebuilt the intake, so I repositioned them both and turned them 90 degrees, as its stated to do, but I still get the code.

Car runs great, except its a dog in second and when going uphill, definitely seems resricted. Any info would be much obliged!

[Noturbuddypal]

05 Subaru Baja NA
266k miles rebuilt engine 60k ago
CEL:P0519

I'm having trouble fixing this idle air control check engine light. Here are all the things I've done or replaced.

2 new idle air valve (not OEM)
2 new neutral safety switch(not OEM)
new throttle position sensor ( properly tuned )
new MAP sensor(not OEM)
new EGR(not OEM)
new 02 sensors ( both OEM)
cleaned throttle body
cleaned PCV valve
idle relearn
adjusted throttle cables
vacuum smoke test ( found one small leak and fixed)
contact cleaner in all connections
cleaned all grounding connections
its been a mixture of me working on it with my limited knowledge and been to a reputable shop. The shop originally put in a new alternator, battery, and battery cables because of a battery light on the dash along with some CEL codes. However they put in a faulty alternator and I drove it home while the voltage was slowly dropping. I was so close to home so did my best to limp her home but battery voltage was seeing 7 volts before I shut her off in the driveway. Towed it back to the shop and put in a working alternator and no issues since besides this one code P0519.I have seen

The code seems to come on after warming up and driving about 40 miles then at some point when I let off the throttle to come to a stop for example the code with light up. It will eventually go away after some time, just to come back.

Not sure where to go from here in trouble shooting and been just throwing new parts at it or having the shop do their best to diagnose not sure where to go from here.
My thoughts are its an electrical issue, or maybe the ECU was damaged from the low voltage?