APPLICABILITY:2000MY Subaru Legacy and Outback 4EAT . 2000MY Impreza 2.5 RS MT5 or 4EAT. 2000/2001 MY Forester MT5 or 4EAT SUBJECT: Front Oxygen (Air/Fuel Ratio) Sensor Subaru of America, Inc. (SOA) has determined that the affected vehicles listed below may experience front oxygen Air/Fuel (A/F) sensor element cracking.The P0420 code has not repeated so far driving it normally under all sorts of conditions. I am still hesitant to call it "fixed' however in the past I would have been able to get the code by now with how I have been driving it. ... We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications ...I've got a 2015 Subaru Forester with 175k miles that runs great but the other day all my dash warning lights went off. I checked the codes and it shows P0700 & P2764 and from a little research online it looks like I need a new transmission valve body. I've erased the codes several times and with each time the first time the car goes from 1st to ...The P0420 CEL code + reduced gas mileage would point me upstream. The rear O2 sensor is good, as it's telling you there too much O2 in the exhaust... as in, you're running too rich. So rich that the CAT can't reduce the O2 levels. That would also explain the poor gas mileage.P0420 is a cat efficiency code caused by the misfires, too much unburnt fuel going through the exhaust. ... MY12 Forester XT 2.5 (Youngest daughter) MY07 Liberty/Legacy 2.5 (Eldest daughter), MY12 Liberty 2.5 (Son in Law) ... How to Read Diagnostic Trouble Codes on 2005 thru 2009 Subaru Legacy and Outback The 2005 thru 2009 model year Legacy ...Forester 2001 L - Stock 101k Miles P0420 - Catalytic Converter Efficiency Below Threshold The forester has been throwing this code for a few months now, typically shows up on long highway runs (but to be fair, that is the vast majority of my driving). I bought a scanner from scantool.net, which I am quite impressed with for $60 new.2012 Forester 2.5X Manual 5spd - 142,309 miles. I bought the car in July 2021 with 116,000 miles. About 8/10 months ago or so, a P0420 code popped up, I did nothing about it for awhile since the car seemed to be running fine. Then a few months ago the car stalled as I was exiting the highway approaching the stop light at the end of the exit ramp.As for it being an intermittent code, thermostat, type of gas, PCV or faulty rear sensor. The CAT could be deteriorating slowly and it's unable to store oxygen to assist in re burning and converting the HCs. If you're in Austin, TX and having difficulties with the dealer or any shop, hit me up. P0420 Diagnosis.Sub2013 Discussion starter. 6 posts · Joined 2021. #1 · Sep 27, 2021. I recently purchased used 2013 Forester and the 2nd day received the dreaded code p0420. This code drives me crazy! This also stops AWD From working and the cruise control.. I would love to know or be able to use my AWD.59 posts · Joined 2015. #1 · May 23, 2020. I'd greatly appreciate some help troubleshooting a P0420 code on my '07 OB. I've reviewed many posts on this, including the P0420 Diagnosis post on the Problems and Maintenance forum, but I'm not understanding some of the basics. Many of the posts refer to checking for exhaust leaks.If you want the P0420 CEL electrical fix, take a look at this link: O2 Foolers, The Economical, ... We’re the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru Forester. Show Less . Full Forum Listing.2.5x_sleeper. 45784 posts · Joined 2007. #6 · Dec 10, 2016. The O2 senor has a heater & if that's faulty, you'd get a specific code pointing to that fault. :wink: If you're getting a P0420 CEL code, the rear O2 sensor is detecting too much O2 in the exhaust flow.My 2011 Forester keep throwing the P04020 code. I reset and it's back in a few days. P0420 Catalyst Efficiency Below Threshold So I get under the car, there are no sensors or wires going to any part of the exhaust system from the engine back. Don't see any oxygen sensor on the pipe. Not sure what is going on.seaholmes said: 2014 Subaru 160k 2.5 l engine. Recently had a promotion at my local oil change shop, where was recommended to take advantage of fuel injector service special. The technician used my brake booster hose as the vacuum to draw in the cleaner, to I assume my intake manifold. Sucking something into the intake manifold is not going to ...We just took care of two recent recalls - valve spring recall and faulty brake light switch/ABS/VDC recall - at a Subaru dealership a couple of months ago. The PCV was also replaced which seems to have stopped excess oil consumption. ... I have a 2014 Forester with 133,000 miles. Recently got the Christmas Tree dash of AT oil temp, hill assist ...However, it is difficult to see the relationship of a defective MAF to the catalyst converter code P0420 since this code involves the O2 sensors. It would explain why the converter ... We’re the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru ...For the last 3 years, several times during the summer, the check engine light comes on for a few hours to a couple of days then goes out, when the weather warms up, never in cold weather. Usually this code or an O2 sensor or both. Usually the light is out when the car sits overnight. For the...2017 Subaru forester with 60 k miles. Already getting the P0420 code and very noticeable loss in power. This Subaru has burned oil from its manufacturing. It's a branded title and I couldn't get subaru to change out the engine. Curious with the low miles if it's just a carbon issue that can be cleaned out of the catalytic converter?Subaru manufactures its cars in two factories, one located in Japan and the other in the United States. Only the Impreza, Legacy sedan, Tribeca, and Outback are produced in the Uni...The P0420 is set because the two O2 sensors are showing the same or close to the same readings. ... We’re the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru Forester. Show Less .UK '01 Manual All Weather Forester. The annoying P0420 reappears between 70 and 200 miles. Two independent exhaust gas tests showed near-perfect lack of pollutants so I ended up looking at the oxygen sensors. ... We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability ...I have a 2010 forester with 2.5 NA motor. I swapped motor bc rod bearings spun. There was a misfire . We replaced plugs, both cats, both o2 sensors, MAF, and leaky EGR.. Car runs great now, BUT, i have check engine, traction,cruise light combo. Oil level is good, motor smoke tested, no leaks... I have a P0171 and P0420.VSurfn. 1329 posts · Joined 2014. #2 · Jul 22, 2018 (Edited) P0420 code stands for “Catalyst System Efficiency Below Threshold (Bank 1).”. When you receive a P0420 code it means your catalytic converter is not operating at maximum efficiency. Usually this means your catalytic converter needs to be replaced and/or your O2 …In my case, after changing the front sensor and working through the symptoms with cardoc on the subaru outback forum, I just bought a $20 code reader and clear the code every two years to pass inspection. ... Forester, Baja, WRX&WrxSTI, SVX ; P0420 code 2011 outback H4 Theme . Default-dark . Default-Light (Default) Contact Us; Powered by ...Subaru Forester owners often find themselves needing to change the clock in their vehicles, whether it’s due to daylight saving time or simply adjusting for a new time zone. While ...May 13, 2023 · The P0420 is a finicky code. There is a range of "acceptable" parameters that Subaru has set. If the O2 sensor sees a value that is outside of that range, even for just a fraction of a second, you get the P0420. Adding the extension doesn't stop the O2 sensor from working, it just doesn't get the immediate read, but more of a mixed read.Dec 27, 2022 · FIXD code detected was P0442 – Evaporative emission control system leak. I had FIXD clear the code prior to taking my 2005 Subaru Forester to a mechanic. The engine light and cruise control lights went out. Today a week later, the lights are back on. I used FIXD and Code P0420 – Catalyst System Efficiency was detected.Hey guys, I recently have been having issues with my 2019 subaru. I went to go get the diagnostic code and it came out p0420. Apparently it's the catalytic converter, but I feel like it's to new of a car to have issues with it.2009 - P0600 and P0420 - Updated! 2009 2.5 4EAT, Premium, 135000 miles. Ive been getting a P0420 for the last year. Even after a new exhaust was installed, including new sensors. Sadly, for me, I just reset the code each time it occurs as the car generally runs "OK". I drive about 70 miles each day (35 miles each way) for a commute …Forester 2001 L - Stock 101k Miles P0420 - Catalytic Converter Efficiency Below Threshold The forester has been throwing this code for a few months now, typically shows up on long highway runs (but to be fair, that is the vast majority of my driving). I bought a scanner from scantool.net, which I am quite impressed with for $60 new.Jul 18, 2017 · Also, P0420 can be the cat, but it can be a number of other things including rear O2 sensor, intake/exhaust leak messing with the air fuel ratio, spark plugs, fuel ...2017-18MY Forester 2.5L 2019-23MY Forester 2018-23MY WRX 2019-21MY Ascent SUBJECT:DTC P0420 Diagnostic Procedure INTRODUCTION: This Service Information Bulletin announces diagnostic service procedures to be followed when DTC P0420 (Catalyst System Efficiency Below Threshold Bank 1) is detected by the Engine Control Module (ECM).My son's outback with 200+ miles had been having the P0420 code pop up on occasion. It would only happen after driving a long distance and only on the way home. I've already replaced both front and rear sensors. ... We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability ...Master. 5,081 Answers. CODE P0420. P0420 - Catalytic Converter Efficiency Below Threshold. This is a catalyst inefficiency code, it is most likely caused by either a bad cat or modified (catless) exhaust. It is unlikely to be a bad 02 sensor. The readings from the rear 02 sensor are used to determine whether to set this code, but if the sensor ...Cats do fail on a regular basis, odd fuel trim/missfire problems destroy the cat, or pinhole exhaust leaks set off the P0420 code. Not so much on Subarus. I see a lot of subaru cat's replaced because of the P0420 code, often with inferior aftermarket cats, and 10 months later the light is back on and the customer is out $600 or more.M. MTpuckstopper Discussion starter. 9 posts · Joined 2023. #1 · Aug 24, 2023. Vehicle Details: 2005 Forester XT. 2005 Forester XT stock except for my son added an Invidia turbo back exhaust. It looks like it is catless and has one O2 sensor. Just had shop try to address the P4020 code without success.Please Like, Comment, and Share. Be sure to subscribe for future videos. Don't forget to hit the bell icon for notifications. YouTube has changed what they s...I got a P0420 code but my voltage was bad due to factory grounds being weak ... Related Subaru Forester Subaru Subaru Cars and Motor Vehicles forward back. r/SubaruForester. r/SubaruForester. This is a place where all Forester owners can meet and discuss Forester news, mods, and general driving experiences whether its track, offroad or daily. ...31 posts · Joined 2006. #1 · Feb 19, 2008. I originally posted a question regarding OBD2 code P0133, but now I have additional info that I could use help on. Ok...there's now been one instance of a P0420 code, catalytic system efficiency below threshold (bank 1), to go along with the intermittent P0133 codes I've been getting.Technical Forums and Vehicle Assistance. Engine Management, Tuning and DataloggingNo matter the situation, Advance Auto Parts has the Oxygen Sensor product you desperately need. We currently carry 13 Oxygen Sensor products to choose from for your 2006 Subaru Forester, and our inventory prices range from as little as $77.99 up to $262.57. On top of low prices, Advance Auto Parts offers 4 different trusted brands of Oxygen ...BTW, the P0420 probably won't clear itself, even if you somehow removed the 'cause'. You need a reader/eraser to do that task (or disconnect the battery for 30 minutes or so ... We’re the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru Forester.Ran the code and got " P0420 - Catalyst System Efficiency Below Threshold Bank 1". ... We’re the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of …The P0420 set the CEL AND made the cruise contrl light blink. The Cel is obvious as to why it was on. The P0420 did that. Now the blinking cruise, On Subaru's with 'drive-by-wire' the cruise control is integrated into the ECU, but is a seperate co-processor. If it detects any engine faults that will cause it to malfuction, it will disable ...Learn more about Subaru Forester at the Edmunds.com Car Forums! Read real discussions on thousands of topics and get your questions answered. ... it only happens under load and between 1500 to 18000 RPMs. And lastly, my check engine light is on, Giving me DTC codes P0420 and P0457. I'm unsure if the codes have anything to do with the noises I'm ...Petrochemical giant Ineos was granted a permit to cut down a wood to build a new plastic plant in Antwerp. A provincial government in Belgium on Thursday (November 7) granted Europ...As to the P0420 CEL code, take a look at these threads: • P0420 - Catalytic Converter Efficiency Below Threshold. • $5 fix (merged thread) As to the O2 sensor, you can research to see what model years use these sensors your '03 uses. :wink: • Front, upstream, Air/Fuel sensor: Denso 234-9015 OEM style.The most common fix for P0420 in the Subaru Impreza is a new catalytic converter, followed by an O2 sensor replacement. Before taking your Impreza into an exhaust shop for an (expensive) new catalytic converter, let's ensure that's what you need. Here's a good P0420 diagnostic order for the Subaru Impreza: 1. Check for Other Codes.Several factors can trigger the P0420 code in a Subaru Forester. Understanding these causes can help in diagnosing and resolving the issue effectively. In detail: Some common causes include a failing or damaged catalytic converter, oxygen sensor issues, exhaust leaks, engine misfires, or even a faulty fuel system.The '$5 fix' does not affect the vehicle's running. Despite minority grumblings to the contrary, it's pretty clear that Subaru added the rear O2 sensor mostly to be OBD-II compliant, and not much more. So, if you back it out of the exhaust stream 1/2", no big deal. Another permanent "fix" is to reprogram your ECU to ignore the P0420 code.For P0420 code, it might be the CAT, or F/A ratio sensor, it might be just replace the F/A ratio sensor to resolve the issue. Since my forester is about 200,000Km, so I just replaced all of them. new head gasket, new timing belt, new CAT and o2s, I'm planning to drive it for another 100,000km. I use Mobil 1 full synthetic oil since day one.P0420, P0031, P0134 - loose spark plug - updated! ('06-'08) Jump to Latest Follow ... Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru Forester. Show Less . Full Forum Listing. Explore Our Forums.2.5x_sleeper. 45859 posts · Joined 2007. #2 · May 17, 2020. @Jaime ochoa welcome to the forum from Oregon! The P0420 CEL code is from the rear O2 sensor, but that doesn't mean the sensor is bad. The rear O2 sensor is monitoring for excess 02 in the exhaust flow, so the fault could be something upstream... even a pinhole leak in the exhaust ...P0420 is the front cat. It's needs to be replaced....and it'll be under warranty.. FREE. TrailAngel 2010 2.5X 5MT. Save Share. Like. J. james gais Discussion starter 13 posts ... Subaru Forester Owners Forum. 2.6M posts 191.2K members Since 2006 We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester ...Dec 19, 2013 · And, a P0420 code really reflects the relationship between the two (front and rear) sensors - not just the rear sensor alone. Depending on your vehicle mileage, your front oxygen sensor may actually be starting to fail - they don't last forever - and the front sensor definitely does contribute to vehicle operation.HELP: Code P0420. My 2009 forester has the “cruise” light blinking and a solid traction control off and check engine light. I got the diagnostics ran and it came out with “P0420: catalyst system efficiency below threshold bank 1”. This happened to me last year but ignored the symptoms for about a month and then had to get it taken in ...P0420 Catalyst System Efficiency Below Threshold; P0171 System Too Lean; P014D Manufacturer Defined - O2 Sensor Slow Response - Lean to Rich (Bank 1 Sensor 1) ... Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru Forester. Show Less . Full Forum Listing.Dec 26, 2009 · 2.5x_sleeper. 45860 posts · Joined 2007. #5 · Dec 26, 2009. My guess is a failing front O2 sensor, causing an over rich condition. This would give you the gas smell & would overwhelm the CAT. The rear O2 sensor, which monitors the CAT, would give you the P0420 CEL code. Sounds like what happen in my '03. :wink:It's normal. Whenever you get a CEL, the Cruise light will flash until the code is reset. If you tried to use your cruise control, it won't work as long as it's flashing. porcupine73. 4729 posts · Joined 2006. #3 · Oct 11, 2009.32 posts · Joined 2015. #11 · Dec 24, 2015 (Edited) P0420 - need some specific help. From what I understand, that rear o2 sensor waveform in the third picture is classic sign of a bad cat. It's likely that waveform that is triggering the code. The others look more stable, unless the scale is off. But the rear still mirrors the front.UK '01 Manual All Weather Forester. The annoying P0420 reappears between 70 and 200 miles. ... We’re the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru Forester. Show Less .Potential Causes of the P0420 Code. Several issues can trigger the P0420 code in your Subaru Forester: Faulty Catalytic Converter: The most common cause, often due to …In all seriousness, the P0420 is only good for making your wallet lighter by either ~$100 for a new sensor or several times that for a new cat. I've never seen a P0420 actually point to a bad catalytic converter. ... We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability ...Jan 29, 2024 · The P0420 code is a common diagnostic trouble code that indicates an issue with the catalytic converter in a Subaru Forester. This code is significant as it can affect the vehicle’s emissions and overall performance. In detail: The P0420 code specifically points to a problem with the efficiency of the catalytic converter.Get ratings and reviews for the top 12 lawn companies in Newington Forest, VA. Helping you find the best lawn companies for the job. Expert Advice On Improving Your Home All Projec...The codes are: P0420: Catalyst System Efficiency Below Threshold (bank 1) P0422: EVAP Control System Leak Detected (Small Leak) I am now in a new area and went to a mechanic who wasn't familiar with my vehicle history. I explained my situation and mentioned to Rear O2 sensor issue of the past. This mechanic read the codes and said that it was ...45853 posts · Joined 2007. #7 · Sep 2, 2022. @SueBrew on your 2001, the rear, downstream O2 sensor function is to monitor the efficiency of the CAT. It's not used by the ECM for engine management, just to give you a P0420 CEL code if too much O2 is detected in the exhaust flow.. Your only issue is that P0420 CEL code, no other CEL …Subaru’s Lineartronic CVT design uses a chain rather than a cable to join the two pulleys of the CVT system as in most other CVT designs.B. bdubbs84 Discussion starter. 13 posts · Joined 2008. #7 · Oct 20, 2008 (Edited) Well, I got rid of the P0420 catalyst code, but now I have two new codes. One is P0440 (Evap. Emission Control System Malfunction) and the other is P0136 (O2 Sensor Circuit Malfunction, Bank 1 Sensor 2). I already have the O2 sensor spacer in place.Forester Code P0420& Hesitation. I have ongoing problem with my 2000 Forester 2,5 Non Turbo with 161K. I have replaced Ignition coil, Spark plugs, fuel filter, wires, ICV sensor, replaced valve cover gaskets, the car has CL with code P0420 but thing is there is no restriction in the exhaust, no soothing, no bad smell, MPG is normal. but I …May 23, 2011 · P0420 is VERY RARELY a failing cat. It is most commonly a failing oxygen sensor (front Subaru, rear any brand), vacuum leak, exhaust leak or what not. Search that code on the forums and you'll find plenty of info. Cats rarely fail without serious mechanical problems, I think your mechanic wants to give you an expensive repair bill.I have this in both my subarus more than a dozen times. Nothing was wrong with the car, the benzin (petrol) was either low octane (lower than the minimum recommended 95) or it had lead for some reason.633. 176K views 8 years ago. This low kilometer Subaru Impreza flags a P0420 Catalyst efficiency fault code very quickly. The rear O2 sensor would behave …Check Engine Light P0420. My check engine light has been going on and off for 2 years. I have owned the car for 2.5. My local mechanic wants to install new catalytic converters. I took it to another shop for a 2nd opinion, 6 months ago. They suggested upstream O2 sensor (one of the 2) was bad and I let them replace it.Sub2013 Discussion starter. 6 posts · Joined 2021. #1 · Sep 27, 2021. I recently purchased used 2013 Forester and the 2nd day received the dreaded code p0420. This code drives me crazy! This also stops AWD From working and the cruise control.. I would love to know or be able to use my AWD.Forester 2001 L - Stock 101k Miles P0420 - Catalytic Converter Efficiency Below Threshold The forester has been throwing this code for a few months now, typically shows up on long highway runs (but to be fair, that is the vast majority of my driving). I bought a scanner from scantool.net, which I am quite impressed with for $60 new.Went to the dealer and said I got a P0455 code. They Cleared the codes and told me it was just a loose gas cap. Again after only 30 days from the last time. Got another P0455 "Evaporative Emission Control system leak detected (large leak)" or "loose gas cap". :shrug: The manual says "turn the engine off and take the gas cap off and back on, and ...Aug 29, 2023 · Air can and does enter cracks or small holes in the exhaust. A system in good shape does not have measurable pressure in it. The exhaust flowing through the pipe can draw ambient air in through openings. A partially blocked converter won't necessarily throw a P0420 code if it is still working as a catalyst.Jan 15, 2017 ... Subaru Outback P0420 Again! Big Lesson ... How to Replace Downstream Catalytic Converter in Subaru Forester and Gain 1200hp ... How to Replace ...No P0420, even after I push the car merging onto the freeway. drove to the next town over. Got dinner. hopped back in started it up and it died shifting into reverse. ... We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the Subaru Forester. Show Less .I was with a friend two months or so ago in her 2021 Forester when she got the "Eye Sight Disabled" message ... and I got the exact same message today in my 2021 Outback Limited ... in both cases it was the same problem. ... To express disappointment with your car or dealership, call Subaru Of America (SOA) 1-800-782-2783 or send them an email ...I have a 2006 Subaru Forester with 95,000 miles on it. Earlier today the CEL (solid) and cruise (flashing) came on while I was driving. I believe it may have occurred as I was accelerating up hill. ... 2006 Subaru Forester: P0420 Catalyst Efficiency Below Threshold Bank Code. Maintenance/Repairs. wvrootmama July 17, 2015, 8:40pm 1. Hello. ...J. Jdave Discussion starter. 7 posts · Joined 2017. #11 · Sep 11, 2019. A code P0420 may mean that one or more of the following has happened: Leaded fuel was used where unleaded was called for (unlikely) A damaged or failed oxygen / O2 sensor Downstream oxygen sensor (HO2S) wiring damaged or connected improperly.2010 Subaru Forester, with P0420 Code. Dealer states the Catalytic converter needs replaced. Question is whether the converter in the pretzel style exhaust line can be replaced without replacing the d … read more. The P0420 on my car was caused by a misfire. SeveThat would help. Write to SOA and state your case. Be su In-dash shows P0700, P1710 and C0140. I used the Bafx and torque pro to clear the codes, it didnt clear the P0700 nor the P1710. This is a first for these codes after the new ECM. Prior to the new ECM codes were P0420 (Cat system efficiency below threshold) P0306 (Misfire cyl 6) and P2503 (Alt Circuit Low). Apr 10, 2011 · Hey all, new to the fourm. I have a Bulletin No: SB-11-124-12. Date of Bulletin: 01/31/2013. Summary Description: SUBARU: INFORMATION PROVIDED REGARDING REPAIR AND INSPECTION OF CAMSHAFT POSITION ISSUES AND ALSO, CHECK ENGINE LIGHT COMING ON, EXTENDED CRANKING OR NO START, ROUGH IDLE. CONDITIONS MAY BE CAUSED BY CAMSHAFT POSITION SENSOR OUT OF SPECIF. Subaru Mechanic: Ronnie. Normally you can replace the front c...
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