P0420 code is the rear sensor reading the O2 levels coming out of the cat are higher than what should be. (possible failing Cat) good sensor. P0136 is the computer reading a problem with the sensor. Just did a PO136 on a ladies 2001 Forester. Changed rear sensor for $124 for part from Subaru and 20 minutes labor.Get ratings and reviews for the top 6 home warranty companies in Lake Forest, IL. Helping you find the best home warranty companies for the job. Expert Advice On Improving Your Hom...Sep 11, 2019 · 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.p0420 catalyst efficiency low bank 1. I have had my check engine light come on and go off several times in the past 9 months, but the last time it came on it did not go off, so I took it to aplace to find out what is the problem, so he hooks it uo to this snap on computer and read the code as p0420 catalyst efficiency bank 1, and he rests it.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 …A P0420 code means your catalytic converter is working with low efficiency. The citric acid bath may be one fix. ... 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.From a little Googling, it seems the P0420 code means the exhaust is rich at the O2 sensor after the catalytic converter. Following that scenario, I would pursue the following possible causes: 1) The O2 sensor is malfunctioning. Nowadays, 100k miles is considered the life of an O2 sensor, and you're well beyond that.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.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...Troubleshooting issues (P0420 surging/poor idle) Update: I'm an idiot! I just recently purchased a 2000 N/A forester 5spd with 240k miles less than two weeks ago. Without going through the whole story I'll just post the facts and then ask my question. PO said head gasket was replaced, no visible signs of leaks can be seen.GET FIXD. What Does Code P0420 Mean? P0420 definition : Catalyst system efficiency below threshold (Bank 1) Issue Severity: MODERATE – Extended driving with this code can cause internal …Here is my story. I have an 01 S with manual trans with 227,000 kms. Forester has always been maintained at the dealer. This past winter I started getting an intermittent P0420 code. If i used premium gas it triggered every 3 weeks or so. If i used regular gas it tripped pretty much once a week ( i fill up approx every 5 days).A P0420 CEL code comes from the rear O2 sensor, usually meaning there's too much O2 in the exhaust. The usual suspect is a leak in the exhaust, or an overly rich condition. ... 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 .P0420 Subaru - Código DTC de falla OBD2. P0014 Subaru - Código DTC de falla OBD2. Deja una respuesta Cancelar la respuesta. Tu dirección de correo electrónico no será publicada. Los campos obligatorios están marcados con * Guarda mi nombre, correo electrónico y web en este navegador para la próxima vez que comente.P0325, P0420, and passing California smog test. For some months now my '02 Forester L has been giving me the P0420 code (and just today it also gave me the P0325). I haven't done anything to address the issue other than to turn off the CEL using my Actron scanner, but now it's time to register my car in California for the first time and so I ...5784 posts · Joined 2018. #2 · Apr 12, 2023. There is a whole thread on this forum about the P0420 code, what can cause it and how to diagnose the cause. If you take the time to read the first 10 to 20 posts of that thread you may be able to diagnose the cause. The code can be caused by bad fuel, faulty O2 sensors, poor electrical connections ...He has many many used foresters for sale and probably has a rebuilt engine ready to go or he can do yours. He is comparably cheap. Ph-717-426-4142. Tell him Al Conrad sent you. The other guy is every bit as good but a bit more expensive and probably doesn't have a rebuilt. He is Subaguru 717-786-2304.3. Subaru & Honda. If you find a P0420 code in your Subaru or Honda, it’s most likely the catalytic converter to blame. It can also be caused by an exhaust leak or a bad oxygen sensor. Check for vacuum leaks or other fuel mixture-related engine codes. Check for any exhaust leaks before the catalytic converter.I'm new to the forum and trying to find answers to a few issues with a 2006 Subaru Forester X I bought about a month ago. First of all, it ... 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 ...35 posts · Joined 2007. #1 · Nov 3, 2007. Two weeks ago I had to have the front O2 sensor replaced on my 2000 Forester. Just last night I got a CEL and went to Auto Zone to check the code. It was P0420 Catalyst Efficiency Below Threshold. Sounds to me like I may have been given a bad sensor at the repair shop or the back sensor is now bad.P0420 Diagnosis Sleeper vdc. Save Share. Like. ... Welcome to the Subaru Outback Owners Forum, we have tons of information about your Subaru Outback, from a Subaru Outback Wiki to customer reviews. Show Less . Full Forum Listing. Explore Our Forums. Gen 5: 2015-2019 Problems & DIY Maintenance Gen 4: 2010-2014 Gen 6: 2020-present Gen 3: 2005-2009.P0065 IS an Air assist failure. The re flash lowers the threshold as detected by the MAP when the valve opens. If it is an electrical failure of the coil, it would be a P0066. But P0065 is a failure of the MAP to see a manifold vacuum change when the ECU signals the Air Assist valve to open.Subaru Forester 2014 I have a cel with code p0420 on and off,CEL came up drove for 70KMS and it went off the moment I had filled in gas. It comes on and off. Should I take it to mechanic or keep driving This thread is archived ... P0420 Code Honda Accord 2016.Why not? In my experience, a P0420 is more a code to prove a bad rear O2 sensor than an actual innefficient cat. How do I know? I threw a P0420 constantly in my Forester. I cleared the code maybe once a week. I finally got tired of seeing the CEL and looking like a NOOB on the street, so I hooked up a 5-gas analyizer.Right now I only have a confirmed P0420 code. My CEL is actually on now. In the past only a pending code would illuminate the CEL. ... 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.Nov 3, 2007 · 35 posts · Joined 2007. #1 · Nov 3, 2007. Two weeks ago I had to have the front O2 sensor replaced on my 2000 Forester. Just last night I got a CEL and went to Auto Zone to check the code. It was P0420 Catalyst Efficiency Below Threshold. Sounds to me like I may have been given a bad sensor at the repair shop or the back sensor is now bad.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.Aug 4, 2022 · How to diagnose code P0420 on a Subaru Forester. Typically, you'll find out about P0420 because your malfunction indicator lamp or "check engine light" turned on & you or a mechanic diagnosed the problem with an OBD II code scanner like this one from Bluedriver. You may experience a very slight reduction in engine power from reduced exhaust ...Catalytic Converter - Subaru (44620AD510) Sale Price: $1,207.79. Make sure this part fits your Car. Add to Cart. Manufacturer Warranty Minimum of 12 Months. Guaranteed Fitment Correct parts guaranteed with vin. Shop with Confidence Your information is safe. In-House Experts We know our products.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.Hi guys.. I too have the same code P0420 on my '01 Forester L, 120K 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 . Full Forum Listing.P0420 Cat below threshold, this has failed due to rich fuel mixture caused by mass air flow sensor and this also damaged the AF sensor. Rear O2 is reading, on removal sensor may be contaminated and if so recommend replacement. ... We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications ...45844 posts · Joined 2007. #4 · Jul 22, 2014. Yes, fixing the P0420 CEL code could improve your gas mileage. The rear O2 sensor on the '03 monitors the exhaust flow for excess 02 & doesn't affect the operation of the engine as it does on the '05+. The P0420 CEL code could be caused by many things, but one is an over rich condition which ...Sep 20, 2015 · The two codes may actually be unrelated. The P0420 is "cat below threshold efficiency". It could mean a bad rear 02 sensor, bad front 02 sensor or bad cat. At dealer pricing, that's $100, $150 and $1000 respectively, just for the parts. P0420 issues will not normally result in rough idle or rough running, unless it really is the front O2 sensor.The cel fires two identical p0420 codes about once a week. I have done a visual inspection and everything seems to be in order. i have a actron super auto scanner and use it under global obdii. ... We're the best Subaru Forester Owners Forum to talk about the best years of the Subaru Forester, modifications and reliability history of the ...Out of the 3 tubes ive remove the outside two and left the middle one on since i believe that from the gas tank. No luck there pumps will still shut off. I also have a check engine light come on with codes P0457 and P0442. Ive searched around and people have replaced the canister and whatever other components are linked to the canister and some ...P0420 is catalyst below efficiency. P0303 is misfire on cylinder 3. The misfire could be contributing to the catalyst problem so it should be addressed first. Pull the # 3 plug and look for carbon or wet with gas. The old plug wires are also suspect. Clean the plug and re-install. Check the connections on both ends of the wire.Nov 3, 2013 · P0420 code, running rich My car, 1999 Forester was giving me fits, running well most of the time, but it started setting the dreaded P0420 code and I noticed that it was running rich, gas mileage dropped to 17 where it usually gets 29 to 31 mpg highway. Also, the idle was wild at times, either idling at 1800, or bouncing between 500 and 1000 rpm.P0325, P0420, and passing California smog test. For some months now my '02 Forester L has been giving me the P0420 code (and just today it also gave me the P0325). I haven't done anything to address the issue other than to turn off the CEL using my Actron scanner, but now it's time to register my car in California for the first time and so I ...The livelihood of 250 million people depend on forest products. Sanjay Kumar Hansda, a member of the Santhal tribe, would usually earn as much as Rs25,000 ($331) between March and ...Forester: check engine light (and cruise light) on after replacing the timing belt. Mechanic says it is the catalytic converter and cost to replace is about $1000 (upstate NY) Report. 2000 Subaru Forester 185,420 mi, Visitor. light is on and i dont think its my cat. think it might be the O2 sensors.. checking it out.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.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.May 14, 2015 · This low kilometer Subaru Impreza flags a P0420 Catalyst efficiency fault code very quickly. The rear O2 sensor would behave almost like the catalytic conver...I've had P0420 since I got the car in june 2011, but didn't bother as, according to my mechanic, "it's just because the computer doesn't recognize the aftermarket catalyst". ... 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'm very new to these Forester hells having just gotten a 2010 and recently got the dreaded P0420 code. In Youtubes suggesting several possible solutions the catalytic converter cleaner added to 1/4 full fuel tank was the first suggestion. Do any of you have successful experience with that, or terrible experience with that like it ate gaskets ...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.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 (oxygen) sensors.DieKeis. 205 posts · Joined 2009. #17 · Jun 28, 2010. I get the P0420 code at irregular intervals. Sometimes on a 6-8 hour road trip I'll get it 2 or 3 times (I reset it with my Scangauge II), other roadtrips I get nothing. And then occasionally it'll pop up on my 7 mile commute - again I reset it.Nov 3, 2007 · 35 posts · Joined 2007. #1 · Nov 3, 2007. Two weeks ago I had to have the front O2 sensor replaced on my 2000 Forester. Just last night I got a CEL and went to Auto Zone to check the code. It was P0420 Catalyst Efficiency Below Threshold. Sounds to me like I may have been given a bad sensor at the repair shop or the back sensor is now bad.When the pressure inside of the fuel tank is too high, P0453, is thrown and the check engine light comes on. If the only trouble code that you have is P0453, your Forester is in no risk of breaking down. The EVAP system is responsible for migrating fuel vapor. Whether it is doing that or not, has no effect on the way your engine runs.Jul 16, 2007 · 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.Here's an Amazon link to that impact gun → http://www.amazon.com/gp/product/B00BWFIKZO/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=1789&creative=9325&creativeASI...When the pressure inside of the fuel tank is too high, P0453, is thrown and the check engine light comes on. If the only trouble code that you have is P0453, your Forester is in no risk of breaking down. The EVAP system is responsible for migrating fuel vapor. Whether it is doing that or not, has no effect on the way your engine runs.Indices Commodities Currencies Stocks11 posts · Joined 2011. #1 · Aug 22, 2011. My 2002 Forester (5-speed) has been having rough idling issues for a month or so now but now it's undriveable due to lagging, jumping, coughing etc. It sounds like a bad Harley tune. One thing that might help diagnose it is that it only has issue when in gear and under load.A P0420 code means your catalytic converter is working with low efficiency. The citric acid bath may be one fix. ... 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.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.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.PO420 code on a 2009 forester. I've gotten this code before and I've read that it's a fairly common thing on Subarus. But my check engine light, no traction control light, and a flashing cruise control light all go off when I drive. This has happened in the past. Last time I replaced the air filter and it went off after letting the car ...P0420 code I have an 03 Forster with 135k mi on it. ... 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. Explore Our Forums.Our family has 3 Subarus. On our 2009 Impreza 2.5i I was getting the p0420 code. We drove it that way for several months not knowing if it was the Catalytic Converter or one of the o2 sensors. I called the local Subaru dealership and they said I would have to pay for a diagnostic and a replacement Catalytic Converter if that was the problem.Subaru Mechanic: Ronnie. Normally you can replace the front converter without having to replace the downstream converter with no issue. The common one to fail and set the P0420 is, in fact, the front converter. If the only code your getting is the P0420 then I would just replace the front converter and usually, you will be fine with no issue.. I figure I'd give this thread a quick update. WeP0420 . Today my 2015 forester threw a P0420 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. P0420 is VERY RARELY a failing cat. It i Jul 24, 2020 · Our family has 3 Subarus. On our 2009 Impreza 2.5i I was getting the p0420 code. We drove it that way for several months not knowing if it was the Catalytic Converter or one of the o2 sensors. I called the local Subaru dealership and they said I would have to pay for a diagnostic and a replacement Catalytic Converter if that was the problem.p0420 does not mean replace cat. it means the rear sensor is not reading that the cat did enough. (which is more likely a old dirty sensor then a cat). I have replaced mine 2x on my 2002 H4 due to p0420, same old original 2002 cal spec cat converter though at 122,000 miles. _____ and one of the ways to light off the cat sensor on the drive cycle: Please Like, Comment, and Share. Be sure to subscribe for fu...
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