[Robin Brown]

So, my 2000 Forester S (155K miles)failed its emissions test last week and the good folk at Firestone want to charge me $599 for a new Catalytic...amongst other things.

My question is, does anyone have any recommendations as to where I should get a non OEM system (catalyticconvertorwarehouse.com?) and if anyone knows of a garage in the Fairfield or Bridgeport CT area who would fit it for me in case Firestone refuse to fit it as I did not buy it from them.

Many thanks in advance.

 

[ddavidv]

Firestone? I trust chain stores about as far as I can throw them. Did it throw a code? P0420, perhaps? That does not necessarily mean you need a cat. I would get a second opinion before doing anything that expensive. There are several threads on the site about cat replacement and a sticky on P0420 you may want to read.

 

[Bravo12]

Yeah, I've been getting that code for over a year. Last year, I cleared the code, drove the car 200+ miles, and got it inspected before the code came back. Doing the same thing this week. Eventually, I need to just get around to replacing the rear O2 sensor, which may or may not be the culprit, but it's a ~$90 possible solution as opposed to a $600+ cat that also may not be the solution.

If nothing else, do a search on these forums for how to use the spark plug spacers from Auto Zone to back-out your O2 sensor so it will read more oxygen and not throw the code. That's a cheap mechanical fix, whether the cat is going bad or not. If that doesn't work, then it's definitely a faulty sensor.

Cheapest solution is what I've been doing. Find someone with a code reader (or go to Auto Zone or similar store that will check/clear your codes for free), and clear the P0420. You will have to drive 200 miles for the OBDII to set-up and show a PASS on the emissions, but hopefully the code won't come back that quickly. Mine generally takes ~500 miles from when I clear it.

 

[funkymonkey1002]

So, my 2000 Forester S (155K miles)failed its emissions test last week and the good folk at Firestone want to charge me $599 for a new Catalytic...amongst other things.

My question is, does anyone have any recommendations as to where I should get a non OEM system (catalyticconvertorwarehouse.com?) and if anyone knows of a garage in the Fairfield or Bridgeport CT area who would fit it for me in case Firestone refuse to fit it as I did not buy it from them.

Many thanks in advance.

Get it inspected at a shop that doesn't do any sort of more major work, such as a quicklube place. They'll just try to sell you on small stuff instead of scamming you for more expensive parts. Do you have a CEL? If not theres a very tiny chance that you would actually need a new cat. You could also probably pick up a cat from someone on the forums for much much cheaper.

 

[mbroadhe]

rockauto.com - Eastern cat
Had the same code myself a few years back. Replaced both o2 sensors only for it to return. I bought the cat from Rockauto, received it in 2 days, put it on, no code since.

 

[Bravo12]

If you do need a cat, it would be cheapest to pick up a universal type online (for about $100) and go by your local Midas or other local muffler shop that can weld it in for you. They will weld in the bungs for the rear O2 sensor. It may still run you close to $200 total, but it's better than a $600+ "genuine" Subaru cat which does the same thing.

 

[mbroadhe]

http://www.subaruforester.org/vbull...-fit-catalytic-converter-2001-forester-60905/

 

[Robin Brown]

Thanks all...after the original 0420 fail I had diagnostics run to specify what the cause of the fail was. The DMV inspection report is very vague....the fail just states P0420: "Catalyst System Efficiency Below Threshold Bank" . Firestone just said "yeah, you need a new CAT, that'll be 600 bucks plus labour".

The Check Engine Light has been intermittent for about three months...on for a day, off for 3 weeks, on for a week, off for two days. Its been on for all the last week and then we had a snow storm here in CT yesterday. I got in the car to drive home from work and the light was out again. I'm sure I don't need to spend big cash but do I get the 02 sensors changed first and then have a re-test? Can I have as many tests done as I like? As

As regards replacing the aftermarket CAT, does anyone have any recommendations of ones that I should avoid as they don't fit? I see prices from around $250 to $75...

Thanks again for all your help.

 

[Bravo12]

If you replace the rear O2 sensor, don't go right back to the inspection place; they may charge you again. Drive it 200 miles and then get someone with a code-reader to check the state emissions on it. My code-reader will show whether or not it will pass OBDII emissions check, so I know before I take it to get inspected.

 

[Robin Brown]

OK...thanks. My plan at the moment is to take it to Autozone or equivalent..have the OBDII reset (or at least have the code confirmed), fit a new 02 sensor, run it 200 miles, take it back to Autozone to check it and then go back to the test centre for the free re-test (assuming all is clear). Is that the order you would do it in?...

I guess the O2 i'll get online...

Cheers.

 

[Bravo12]

OK...thanks. My plan at the moment is to take it to Autozone or equivalent..have the OBDII reset (or at least have the code confirmed), fit a new 02 sensor, run it 200 miles, take it back to Autozone to check it and then go back to the test centre for the free re-test (assuming all is clear). Is that the order you would do it in?...

I guess the O2 i'll get online...

Cheers.

Yeah, that's the plan. Any Subaru dealer's parts counter can get you the O2 sensor. Hopefully, mine is ready to go after work today.

 

[Robin Brown]

Thanks...I'll let you know the outcome.

Cheers...

 

[singincanary]

Great prices on parts contact Jackie at Annapolis Subaru. Great prices, quick shipping. 443-837-1422.

 

[ddavidv]

This mimics our '02's P0420 nonsense pretty well. I suggest you do the "mechanical fix" with the spark plug anti-foulers. Many people have replaced the aft sensor with no improvement, and that sensor isn't what I'd call cheap. The Fix has completely eradicated any further CE codes and the car runs fine (so no mega-dollar cat converter replacement!).

 

[Robin Brown]

Thanks, I may try that...I need to search under the $5 fix thread right?...

Your're right, the sensor isn't cheap and I have my doubts that there's anything really wrong with the CAT. I'm not a regular customer at the garage I took the Forester to and I have a feeling they were looking for work.

One question, if the Check Engine Light is intermittent do you think that points more towards an inefficient sensor than an actual CAT problem?

Cheers...

 

[ArcadeTom]

Thanks, I may try that...I need to search under the $5 fix thread right?...

Your're right, the sensor isn't cheap and I have my doubts that there's anything really wrong with the CAT. I'm not a regular customer at the garage I took the Forester to and I have a feeling they were looking for work.

One question, if the Check Engine Light is intermittent do you think that points more towards an inefficient sensor than an actual CAT problem?

Cheers...

The intermittent sensor is what is "tripping" me up on this one. You said you drove home in the snow and the light went out? Have you gone under the car and inspected what the wiring and plug look like on the O2 sensor? It could be as simple as a bad place in the wire or a loose connection.

 

[Robin Brown]

Thanks...I haven't checked on anything being loose. Although I did pay Firestone for diagnostics when I first took it in (and it failed the Emmissions Test) I'm not sure they even looked under the car!

The intermitent-ness (sic) is what is confusing me. I haven't had the OBD reset, and haven't really hammered it down I95 for a week or so but the light just went out again after the snow on Thursday. I know at some stage next week the CEL will come right back on again for a few days.

I have 35 days before I have to resubmit the Forester for a Emmissions Re-Test so I've got time to look at a bunch of options....hopefully none of them will involve replacingthe CAT...

 

[funkymonkey1002]

P0420 basically means that the rear O2 isn't seeing the value it should see based off what the front o2 is telling the car. This is usually an issue with the rear o2 sensor. However, your front o2 could also be failing, but still be within spec so its not throwing its own code.

 

[Robin Brown]

OK...thanks. Seems to me the common thought here is that the issue that is throwing the 4020 code is most probably the 02 sensor. I have a reference for a local (independant) garage from a freind. I'll take the car up to them to take a look at the sensor and the DMV Emissions Report from Firestone next week...

Cheers.

 

[ddavidv]

The code comes from the rear sensor. Techs who are not familiar with Subarus and think the code is to be obeyed like the word of God himself will diagnose it as a bad cat. It is entirely possible the cat may be contaminated, especially if the car ever had bad HG's. But, if it runs fine my desire to run 'green' is negated by the drain on my bank account to replace a component that is not hurting the actual performance of the car.

The CE light may not be constant...it would come and go on ours but the P0420 code would still be stored in the computer. I'd erase it, and it would return anywhere from a few days to a few weeks. Since doing the 'fix', it has not returned once.

I have the opinion that if the rear sensor is triggering the code, the sensor itself is likely okay. The front one does a lot more reading to set the engine tune. I think the rear one is mostly an on/off switch for the CE light, but that's just speculation on my part.

Link to the $5 fix: http://www.scoobymods.com/rear_o2_sensor_fix-t5468.html?t=5468