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Showing results for tags 'P0420'.
Found 5 results
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Installed an L-shaped spacer (3 x 3 inches) at the second O2 sensor on a 2000 Forester, to lay to rest the P0420 code that has been coming on weekly for the last five years! Now I'm getting a P0136 code. My understanding was that the O2 sensor distal to the cat served no critical purpose, other than to warn of poor emissions. But some P0136 code explanations suggest that the ECU may interpret P0136 as a lean fuel/air state. Is this true for a 2000 Forester? Should I shorten the spacer to avoid a P0136 call? Both original O2 sensors were replaced with new ones a couple years ago. -
Need some advice, I have a Subaru Outback 2000 with over 250,xxx Miles. Codes: P0420 and P0303 When I initially ran the reader it said the O2 sensors were bad, both front and back. I replaced those hoping it would eliminate the 420 code also but it has not. Though, the O2 sensor codes did go away. Any advice on what would be good to check before outright replacing the Cat? As for the 303 code I was advised that this is probably related and will go away once the 420 code is eliminated. The car doesn't run well. It lacks power and often stutters while accelerating, sometimes almost violently if the AC is on. My Battery has had some issues with a bad connection that I have to tighten frequently because someone overtightened it. Anything helps! -
I have a 2005 outback llbean 3.0 with 146,000 miles. Today the check engine light came on with a blinking cruise control light. Had the code pulled at Advance which said P0420 Catalyst system efficiency below threshold What is the fix? O2 sensors? up or down stream is there a way to determine? Best place to purchase and what brand? I assume down stream by the wording of the code?? Suggestions are greatly appreciated. I did replace the pcv valve about 1000 miles but not OEM. Also I believe there are oil leaks around the valve covers that should be fixed. Thanks in advance for your wisdom. gerald in NC 2005 subaru outback llbean -
OK a little late on maintenance at 135K miles, I decided to check out the fuel filter. Turns out the only fuel filter is a "sock" inside the gas tank and according to SOA tech "we never change them". Anyone change/examine yours? While on the subject, this week I will be visiting a mechanic to track down the cause of an elusive P0420 that a data log interpretation is pointing to either vacuum leak or poor fuel delivery (perhaps both if I'm really unlucky?). Mechanic plans on "smoking" the car in search of any vacuum leak and then checking fuel pressure. Would you check pressure first or it doesn't matter? Few questions: 1. Can a fuel pump be failing (weak) without obvious symptoms over a period of 2 years and 30K miles? Since the dealer doesn't stock the pump, is this easily replaced? Any directions appreciated. 2. Where is the fuel pressure regulator? Same question about failing/weak fuel pressure regulator symptoms?? 3. Can the "sock" filter become coated and therefore ineffective? Doesn't look like it is replaceable. -
Okay so here is my question, I have a 2001 Lego 5 speed with 125,xxx miles on her, and Is there any difference between O2 sensors for the automatic and manual? On Subaru Parts For You it lists that there are two different O2 sensors as seen here: http://subarupartsforyou.com/cp_partlistbymod.php?model=Legacy&subcat=Sensor%2C+Oxygen&year=2001 I just wanted to know of this was true or not because my car has the dreaded P0420 code and I have done everything to get if off such as running NGK spark plugs, OEM Beck Arnely wires, OEM coil pack when the original one went bad, new air filter, fuel filter, intake gaskets, head gaskets, and I already did a timing belt kit on it when it hit that interval including thermostat (used the proper one, not the ordinary one) water pump, and I'm running good 89 octane gas threw her. So the only thing left is to change the front O2 sensor and I have a used one that was good out of a 2000 outback but it was an automatic so I'm not sure if they would interchange. I'm going to try the seafoam trick tomorrow to see what that does. My New York state inspection is up in a couple of months and it needs to pass the OBII check being 1996 and newer...good ol' NYS!!!