Author Topic: Any hope of cheaply fixing my catalytic converter issue?  (Read 8738 times)

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Any hope of cheaply fixing my catalytic converter issue?
« on: March 04, 2016, 08:07:29 AM »
I humbly come to pick the collective mustachian brain again. My check engine light came on yesterday, so I rushed to the Subaru dealership to get it checked out. I have a 2008 Impreza. The verdict is that I need a new catalytic converter, and just as a bonus, the head gaskets are also leaking badly (but I already knew that was becoming a problem--I'll find a local mechanic to fix this for me).

The estimate on the CC is $1300! I don't want to be a bad citizen creating more pollution than I already do, so I do want to get it fixed (preferably before my inspection is due in May). Is this one of those cases where the dealership really should fix it or should I shop around? How long can I drive around without fixing it (I've heard some cars stop running if the CC doesn't work)? Does the whole thing always have to be replaced or can a part sometimes get replaced? Is there anything else I should know before I naively pull out my wallet?

Just so you know, I'm not a DIY-er when it comes to the car. Wish I were, but that's just not gonna happen. I'm mainly looking for a little knowledge so I don't get ripped off as I figure out who to pay to fix this for me. Thanks for any tips!



Nate R

  • Bristles
  • ***
  • Posts: 341
  • Age: 34
  • Location: Milwaukee, WI (Bay View)
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #1 on: March 04, 2016, 08:41:52 AM »
There are often generic branded cats available that will be cheaper. The whole CC has to be replaced. Sometimes those don't play well with particular car models, though. I'd check some Subaru forums online for any info about this, and maybe check with a couple independent garages on pricing for cat replacement before you pull the trigger.

Don't do the cat without doing the head gasket. The leaking head gaskets could, in theory, help accelerate cat life and clog it up/wear it out prematurely.

In fact, it's slightly possible that the bad cat code is somewhat false, due to the head gasket issue.

Usually, the car is comparing the signals from the oxygen sensor before the cat and the oxygen sensor after the cat to make sure they're different enough to verify the cat is doing its' job. But I could see a bunch of oil or coolant in the exhaust (from the leaking head gaskets) screwing up the O2 sensor reading.

Hope that helps!

Gone Fishing

  • Magnum Stache
  • ******
  • Posts: 2754
  • So Close went fishing on April 1, 2016
    • Journal
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #2 on: March 04, 2016, 08:57:54 AM »
First, are you required to have a clear CEL to pass an inspection?  If not, drive on. The likelihood that the materials and energy required to manufacture, transport, and install a cat off set the remaining emissions from a car that is in it's "twilight years" is doubtful.   

If your local requires a clear OBDII to legally drive your car, start by getting yourself a little Actron Pocket code reader off Amazon (or elsewhere) for $40.  I recently got one and don't know why I waited so long.  Driving Mustachian cars will almost certainly require check engine light attention from time to time. 

Next, did the stealership reset the code?  If not, use your new little code reader to do it yourself.  About 50% of the time CELs are simply glitches and will go away once the code is cleared.  Very cold weather will set mine off from time to time.  It warms up and everything is fine. 

My wife's car has a Cat that is on the ragged edge of efficiency.  Sometimes the on board diagnostic is fine with it, other times it will pop a code.  A clear OBDII system is required to pass inspection and legally drive a vehicle in our county so around a month before the car is due for inspection, I clear the code and cross my fingers that the OBDII will be happy with it for another year.  This has worked for the past 2 years.         

NoStacheOhio

  • Handlebar Stache
  • *****
  • Posts: 2143
  • Location: Cleveland
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #3 on: March 04, 2016, 09:04:25 AM »
The catalityc converter is an emission item and should be warrantied for 8 years or 80miles because of California laws.  I know you have a 2008, but what is the production date on it?

Is it from production date or sale date? Other warranty items start with the original sale date.

Edit: replacing the cat isn't one of those "must do at dealership" items. I would find a good exhaust/muffler shop, and get a quote from them.

Jack

  • Magnum Stache
  • ******
  • Posts: 4734
  • Location: Atlanta, GA
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #4 on: March 04, 2016, 09:05:59 AM »
Don't do the cat without doing the head gasket. The leaking head gaskets could, in theory, help accelerate cat life and clog it up/wear it out prematurely.

In fact, it's slightly possible that the bad cat code is somewhat false, due to the head gasket issue.

Usually, the car is comparing the signals from the oxygen sensor before the cat and the oxygen sensor after the cat to make sure they're different enough to verify the cat is doing its' job. But I could see a bunch of oil or coolant in the exhaust (from the leaking head gaskets) screwing up the O2 sensor reading.

+1!

I've always heard that exhaust work is kind of like drywall: it requires practice to get right yet is cheap to pay somebody to do, so it isn't worth it to DIY.

However, that assumes welding; if your cat is bolted in instead of welded then you probably could just do it yourself. It looks like replacement cats for your car -- both of them, as it appears a 2008 Impreza contains two -- come as bolt-on assemblies.

I don't know enough about how an Impreza boxer engine is packaged within the engine bay to know if replacing that front cat would be a complete pain in the ass or not (e.g. because it requires dropping the engine out of the car or something), but if it isn't, then it seems like it could be reasonable to DIY.
« Last Edit: March 04, 2016, 09:07:56 AM by Jack »

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #5 on: March 04, 2016, 09:18:01 AM »
So Close: I don't know about the clear CEL to pass inspection in my county--will have to research that.

NoStache and craige: How would I find the production/sale date? I bought the car used in 2010 so I don't know anything about its life before I got it. Wouldn't the dealership have been required to tell me if it was still under warranty?

There's no way I'm trying to do this myself--the time and expense to figure it out myself, buy tools, etc. would render it unmustachian for me to try it! But, if it's not actual rocket science, then maybe I can find a non-dealership person to do it that would cost less.

Jack

  • Magnum Stache
  • ******
  • Posts: 4734
  • Location: Atlanta, GA
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #6 on: March 04, 2016, 09:24:59 AM »
There's no way I'm trying to do this myself--the time and expense to figure it out myself, buy tools, etc. would render it unmustachian for me to try it! But, if it's not actual rocket science, then maybe I can find a non-dealership person to do it that would cost less.

If it's the second cat that went out, then it looks like the only tools required are jack stands and a socket set (and probably some penetrating oil to get the bolts un-seized), and the steps required are (1) put car on jackstands, (2) unbolt old cat, (3) bolt on new cat, (4) lower car back to ground. That's if it's the second cat.

If it's the first, the procedure is probably much more complicated and I agree it'd be worth paying a third-party shop to do it.

TheGadfly

  • 5 O'Clock Shadow
  • *
  • Posts: 97
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #7 on: March 04, 2016, 09:35:47 AM »
If your local requires a clear OBDII to legally drive your car, start by getting yourself a little Actron Pocket code reader off Amazon (or elsewhere) for $40.  I recently got one and don't know why I waited so long.         

+1

My CC is also setting off my check engine light after a malfunctioning oxygen sensor dumped excess fuel into the CC. Long story: http://www.fitfreak.net/forums/1st-generation-gd-01-08/90494-2007-honda-fit-sputtering-jerking-misfiring-resolved.html. Anyway, before going to a mechanic, I bought an OBDII code reader and did some investigating myself and found that my CC isn't completely ruined but it is "operating under threshold" which means that it does work to some extent, just not optimally. The same may be true for your car so i wouldn't worry too much about being a big polluter.

Since this issue doesn't impact performance and the state of Michigan doesn't have emissions tests, I just drive with the check engine light on.

I would like to replace the CC at some point but the car is so old that I don't want to drop $1000+ on it. I'm on the lookout for a salvaged CC that my local mechanic can slap on (although, these are hard to come by and are still about $400). My own research revealed that the non-honda or universal cats do not last very long and are not even legal in some states.

JZinCO

  • Pencil Stache
  • ****
  • Posts: 701
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #8 on: March 04, 2016, 09:51:57 AM »
Some random thoughts...
Unfortunately cats are not a cheap item to deal with. I've had to pay $400 to a shop to put a cat and muffler into a straight pipe. I could have paid a backyard welder much less but I was self-pressured to get it done right and pass emissions asap. I also decided to get flow-through cat and muffler put on so that increased the price significantly. I have found muffler shops to vary significantly on cost so I advise OP to call around.
 You generally have to buy an OEM though it doesn't have to be a dealer part. Finding a universal one can be tricky because you may run into issues if you get the overall box's dimensions wrong or you are wrong about the inside diameter of the exhaust pipe both inflow and outflow. It is unlawful to put on an old cat and they will catch that during emissions testing. On that note, ask for the cat back after replacement because you can make a few $$ at a scrapper. You cannot legally sell your cat to a private person even if you sell for the purposes of scrapping.
Someone else mentioned something about the OBDII codes. You can clear them by disconnecting the battery. You don't need to use a scanner to do this. Alot of people who live in states with inspections (I don't. I just have emissions testing) whose cars throw codes will disconnect the battery and then try to drive just long enough to warm up the motor but not long enough to re-throw the code. Then again, I've never owned a 2000+ vehicle, so maybe new ECU's hold on to their memory without power?

There's no way I'm trying to do this myself--the time and expense to figure it out myself, buy tools, etc. would render it unmustachian for me to try it! But, if it's not actual rocket science, then maybe I can find a non-dealership person to do it that would cost less.

If it's the second cat that went out, then it looks like the only tools required are jack stands and a socket set (and probably some penetrating oil to get the bolts un-seized), and the steps required are (1) put car on jackstands, (2) unbolt old cat, (3) bolt on new cat, (4) lower car back to ground. That's if it's the second cat.

If it's the first, the procedure is probably much more complicated and I agree it'd be worth paying a third-party shop to do it.
That looked wrong to me but I did a google search and found some high performance vehicles actually have a secondary cat.
« Last Edit: March 04, 2016, 09:54:58 AM by JZinCO »

FerrumB5

  • Pencil Stache
  • ****
  • Posts: 521
  • Location: Illinois
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #9 on: March 04, 2016, 09:57:59 AM »
CEL on will automatically fail the emissions test I believe. They won't even hook the tester up. Never try to clear OBD codes and try to pass emissions test. They require at least 48 hours after the last code was cleared, no matter what code that was

JZinCO

  • Pencil Stache
  • ****
  • Posts: 701
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #10 on: March 04, 2016, 10:00:33 AM »
CEL on will automatically fail the emissions test I believe.
*Depending on state and model year

Jack

  • Magnum Stache
  • ******
  • Posts: 4734
  • Location: Atlanta, GA
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #11 on: March 04, 2016, 10:17:36 AM »
Then again, I've never owned a 2000+ vehicle

...

That looked wrong to me but I did a google search and found some high performance vehicles actually have a secondary cat.

Secondary cats have become increasingly common on newer vehicles, in order to meet increasingly stringent emissions standards. "High performance" (in terms of power relative to fuel use) has essentially become the baseline. Even cars like the Prius have compression ratios up into the 12-13:1 range these days.

JZinCO

  • Pencil Stache
  • ****
  • Posts: 701
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #12 on: March 04, 2016, 10:27:02 AM »
Thanks, my mechanical knowledge stops at MY1995.
It's like asking a hand tool woodworker to use powertools  :)
« Last Edit: March 04, 2016, 10:29:01 AM by JZinCO »

FerrumB5

  • Pencil Stache
  • ****
  • Posts: 521
  • Location: Illinois
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #13 on: March 04, 2016, 10:32:15 AM »
Thanks, my mechanical knowledge stops at MY1995.
It's like asking a hand tool woodworker to use powertools  :)

Starting mid-90s, 1996 IIRC, OBD-II is standard on all vehicles (does not apply to VAZ models back then). Gradually, emission tests went from pipe tests to OBD ones almost everywhere in the US at least

acroy

  • Handlebar Stache
  • *****
  • Posts: 1702
  • Age: 42
  • Location: Dallas TX
    • SWAMI
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #14 on: March 04, 2016, 11:21:43 AM »
A failed cat is a symptom, not a cause. They will last the lifetime of the car, as long as the engine is operating correctly. “Look upstream” for the cause.

That said, the O2 sensor is likely just bad. It is common (unfortunatly) for a car to come in with a check engine light caused by a failed $40 sensor, and the shop to quote a $1000+ cat. My sister paid $1400 for ‘new’ cat when the check engine light came on. 2 months later the light was back on. $40 sensor and the light went off…..

The sensors are ‘quoted’ to last 50-100k. The last one I changed went 140k.

Clearing codes: purchase the gizmo above, or better, a Bluetooth OBD2 adapter and the $5 Torque app for your smartphone. It can clear codes etc. If no smartphone, then just stick with the wired code reader.

Good luck! wish you were local, I could help you out.

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #15 on: March 04, 2016, 11:28:21 AM »
It would be great if it was just an O2 sensor. I'm going to go to a local autoparts place and let them read the codes again (since the dealer didn't give me any info on that). Will that tell me whether the whole cat needs replacing or just the sensor?

JZinCO

  • Pencil Stache
  • ****
  • Posts: 701
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #16 on: March 04, 2016, 11:29:24 AM »
Thanks, my mechanical knowledge stops at MY1995.
It's like asking a hand tool woodworker to use powertools  :)

Starting mid-90s, 1996 IIRC, OBD-II is standard on all vehicles (does not apply to VAZ models back then). Gradually, emission tests went from pipe tests to OBD ones almost everywhere in the US at least
Yeah hence I said 95 :) My joke fell flat. I mean to say I understand vehicles where problems are generally electric or mechanical rather than electronic, not to mention the myriad of improvements/complexities.
My state still does either dyno with pipe or roadside air quality testing for me because I run old vehicles. They only changed to OBD testing last year in my state for vehicles 2000 on up (in fact now all vehicles <7 yr old are exempt from emissions).

JZinCO

  • Pencil Stache
  • ****
  • Posts: 701
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #17 on: March 04, 2016, 11:37:45 AM »
It would be great if it was just an O2 sensor. I'm going to go to a local autoparts place and let them read the codes again (since the dealer didn't give me any info on that). Will that tell me whether the whole cat needs replacing or just the sensor?
IIRC, there are different codes for o2 sensors (PO2xx) than for cats (PO4xx).
What evidence did the original evaluation have for saying the cat was bad? Just a code being thrown? That could signal sub-optimal but still sufficient performance. You can also do a visual check. Some issues will cause actual signs on the exterior of the cat such as a bronzing coloration.

BDWW

  • Bristles
  • ***
  • Posts: 482
  • Location: MT
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #18 on: March 04, 2016, 11:59:54 AM »
$1000 is absurd, a exhaust shop should be able to put one in (universal weld in cat) for $400 or less as someone above mentioned.

If your brave/handy, the Impreza is a highly modded car. There are lots of parts available.

You didn't mention model, but I assume its not turbo,

Something like this might be just what you need.
http://www.summitracing.com/parts/wlk-55585/applications/year/2008/make/subaru/model/impreza


FerrumB5

  • Pencil Stache
  • ****
  • Posts: 521
  • Location: Illinois
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #19 on: March 04, 2016, 12:23:33 PM »
Yep. If it's not welded but bolted - this is the way to go if you have more or less straight hands

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #20 on: March 04, 2016, 01:52:16 PM »
I'm not getting satisfying answers from anybody I talk to locally, but the Subaru dealership told me it's a P0420 code. Does that mean anything to anyone? When I google it, it sounds like it could mean a number of things. I'm worried that I'm going to pay for this expensive repair but that some other "upstream" problem will just cause it to happen again.

FerrumB5

  • Pencil Stache
  • ****
  • Posts: 521
  • Location: Illinois
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #21 on: March 04, 2016, 02:03:43 PM »
P0420 could be the 2nd oxygen sensor, or could be a mere misfire. We cannot say exactly what it is over internet, unfortunately. Try clearing the code and flooring the car on an empty highway where you expect no police for a few seconds. The high revs could clear some old residues in the system

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #22 on: March 04, 2016, 02:29:31 PM »
Ferrum, I just got off the phone with someone who recommends fixing the head gaskets and seeing if that doesn't help resolve the CC issue. He says that leaky gaskets can cause issues that can affect the exhaust which could affect the CC (or maybe the oxygen sensor?). So, maybe I can just fix the head gaskets, clear the codes, and see if the CEL comes on again.

I appreciate all the tips from you folks!

FerrumB5

  • Pencil Stache
  • ****
  • Posts: 521
  • Location: Illinois
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #23 on: March 04, 2016, 02:58:37 PM »
That is possible, in fact. Leaking gaskets send some oil into combustion and hence into exhaust making the second o2 sensor complain. Replacing a HEAD gasket is a relatively easy job unlike a block gasket

JZinCO

  • Pencil Stache
  • ****
  • Posts: 701
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #24 on: March 04, 2016, 03:48:45 PM »
So, maybe I can just fix the head gaskets, clear the codes, and see if the CEL comes on again.
Look before you throw down cash. Get under the car, look at the cat (discoloration?) and also the sensors (loose, frayed wires).
Also, I'm not sure if the shop told you but it is standard practice that if there is a problem upstream which ruins a new cat then you are SOL. So best to fix a potential root cause then to ruin a new cat.

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #25 on: March 05, 2016, 09:04:27 AM »
JZ, can you explain what some of the "upstream" issues are that I should worry about?

Nate R

  • Bristles
  • ***
  • Posts: 341
  • Age: 34
  • Location: Milwaukee, WI (Bay View)
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #26 on: March 05, 2016, 10:14:12 AM »
JZ, can you explain what some of the "upstream" issues are that I should worry about?

I assume JZ was referring to the leaking head gaskets.

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #27 on: March 07, 2016, 01:50:48 PM »
That's what I've decided to go with--fixing the head gaskets and then seeing what happens with the cat. Thanks again, y'all!

Gone Fishing

  • Magnum Stache
  • ******
  • Posts: 2754
  • So Close went fishing on April 1, 2016
    • Journal
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #28 on: March 07, 2016, 02:59:49 PM »
That is possible, in fact. Leaking gaskets send some oil into combustion and hence into exhaust making the second o2 sensor complain. Replacing a HEAD gasket is a relatively easy job unlike a block gasket

Not disagreeing, but I once had a Honda Civic with a blown seal or ring somewhere, it'd burn oil to the tune of a quart per tank of gas (but didn't leak a drop!). When I drove it, I said I was "foggin' for skeeters" but it ran clean once it warmed up.  The shop told me it wasn't worth fixing given the age and number of miles on the car.  Ironically, it never threw a code of any sort despite somewhere in the neighborhood of 170 quarts of oil going through the cat.

Nate R

  • Bristles
  • ***
  • Posts: 341
  • Age: 34
  • Location: Milwaukee, WI (Bay View)
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #29 on: March 07, 2016, 07:33:07 PM »
What year was that Civic?

Gone Fishing

  • Magnum Stache
  • ******
  • Posts: 2754
  • So Close went fishing on April 1, 2016
    • Journal
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #30 on: March 08, 2016, 08:10:05 AM »
What year was that Civic?

1997

Were the early OBDII's less sensitive?

Nate R

  • Bristles
  • ***
  • Posts: 341
  • Age: 34
  • Location: Milwaukee, WI (Bay View)
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #31 on: March 08, 2016, 08:40:50 AM »
What year was that Civic?

1997

Were the early OBDII's less sensitive?

Was thinking it might be OBDI. Not sure if early OBDII's were less sensitive, but I also wonder if things are different when there's 2 cats, like in the Subaru in question. In that case, the first cat is in the exhaust header, so there's not much time for oil and such to drop out of the exhaust stream....


TXScout2

  • 5 O'Clock Shadow
  • *
  • Posts: 66
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #32 on: March 08, 2016, 09:56:14 AM »
At least in my state, the car will pass inspection in a situation where a single monitor reads "not ready," so long as all the other monitors are reading "Pass."  My car was giving off a "Fail" for the Catalytic Converter, but after a reset, the Cat monitor would read "Not ready" for a day or two before finally reading "Fail".  So for 3 years, I would reset the computer, drive the car for about a day, until all the monitors were "Ready" except the Cat, and then go get an inspection and pass.   

Progressively the Cat monitor began to read "Fail" more quickly, until it would read "Fail" before the other monitors would read "ready," and I couldn't pass inspection.  So I had the cat replaced with an aftermarket one by a shade tree mechanic for about $300.  Didn't repair anything else.  Been driving with that replaced Cat for about 18 months now and it hasn't spit a code yet.

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #33 on: March 09, 2016, 12:59:27 PM »
Here's what I did: got the shop (not the dealership) to fix the head gasket issue and clear the CEL so we can see if that gets triggered again. That job ran me under $1000, which is considerably less than the dealership wanted. I'll just watch and wait to see if that code pops back up again.

Several folks have suggested that I get some kind of stuff that I would add to the gasoline to help clean stuff out, but when I looked at all the stuff on the shelf, I had no idea what to pick. Any suggestions for an additive that would help with this (like a specific brand, etc.)? Additionally, folks have told me to run a higher octane gasoline and avoid the ones with ethanol, but I always thought the Car Talk guys said that higher octane was bogus. Thoughts?

acroy

  • Handlebar Stache
  • *****
  • Posts: 1702
  • Age: 42
  • Location: Dallas TX
    • SWAMI
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #34 on: March 09, 2016, 01:13:48 PM »
Highly recommend running a can of Seafoam through it,
pour it into a 1/4 tank gas and run it till you have to fill up. Great way to clean up the fuel system.
Run regular unleaded gas and don't worry about it. The car is late model and will take care of itself.

Nate R

  • Bristles
  • ***
  • Posts: 341
  • Age: 34
  • Location: Milwaukee, WI (Bay View)
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #35 on: March 09, 2016, 02:59:11 PM »
Agreed, Sea Foam might help a bit. Don't bother with the higher octane fuel or non-ethanol for a 2008.

I like your actions on this so far, seems like a good plan!

Jack

  • Magnum Stache
  • ******
  • Posts: 4734
  • Location: Atlanta, GA
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #36 on: March 09, 2016, 03:04:28 PM »
FYI, SeaFoam comes in a couple of varieties: A can that you pour liquid out of and an aerosol spray. For the purpose acroy and Nate R mention, you want the liquid pour version and you want to follow the instructions for adding it to the fuel, not the oil.

otter

  • Stubble
  • **
  • Posts: 105
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #37 on: March 10, 2016, 11:09:44 AM »
I do not know where the OP lives (it sounds like they live in the US, but the state isn't mentioned), but it is worth mentioning that not all catalytic converters are created equal. Aftermarket cats generally do not perform as well as OE cats. In most states, this can often be ignored because they do well enough. However, in CA and other states that use CA's emissions rules, cats must be approved for use in California, as indicated by a sticker (and CARB database.) These are, unsurprisingly, expensive. Sometimes a good used OE cat can be more cost-effective than a new aftermarket cat. For ordinary cars this can be difficult to find; for cars with an enthusiast following (possibly including the OP's Subaru) less so.


Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #38 on: March 11, 2016, 07:36:08 AM »
I saw Seafoam on the shelf, but there were several different versions of it and I didn't want to do something dumb and have even more car trouble! Is this what I'm looking for:

 http://www.lowes.com/pd_10730-53212-SF16_0__?k_clickID=9444fcaa-66ca-4be2-9f6e-ae59a474f45a&store_code=1522&productId=4221987&selectedLocalStoreBeanArray=%5Bcom.lowes.commerce.storelocator.beans.LocatorStoreBean%4054e354e3%5D&storeNumber=1522&kpid=4221987&cm_mmc=SCE_PLA-_-ToolsAndHardware-_-AutoAndGarageSpecialty-_-4221987%3ASea_Foam&CAWELAID=&CAWELAID=1709308725

So far, the CEL has not come back on, but I haven't driven a lot since the head gaskets got fixed. Fingers crossed!

Jack

  • Magnum Stache
  • ******
  • Posts: 4734
  • Location: Atlanta, GA
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #39 on: March 11, 2016, 07:54:53 AM »
I saw Seafoam on the shelf, but there were several different versions of it and I didn't want to do something dumb and have even more car trouble! Is this what I'm looking for:

 http://www.lowes.com/pd_10730-53212-SF16_0__?k_clickID=9444fcaa-66ca-4be2-9f6e-ae59a474f45a&store_code=1522&productId=4221987&selectedLocalStoreBeanArray=%5Bcom.lowes.commerce.storelocator.beans.LocatorStoreBean%4054e354e3%5D&storeNumber=1522&kpid=4221987&cm_mmc=SCE_PLA-_-ToolsAndHardware-_-AutoAndGarageSpecialty-_-4221987%3ASea_Foam&CAWELAID=&CAWELAID=1709308725

So far, the CEL has not come back on, but I haven't driven a lot since the head gaskets got fixed. Fingers crossed!

Yes, that's the right Seafoam. (The wrong one is the one with a straw taped to the side of it.)

FerrumB5

  • Pencil Stache
  • ****
  • Posts: 521
  • Location: Illinois
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #40 on: March 11, 2016, 01:24:06 PM »
For Seafoam lovers - pls be aware that the gunk that was stuck to the head walls etc could be washed into rather narrow oil canals that are designed to lube vital engine parts and clog them. Exact analogy to a stroke when a blood clot clogs the blood vessel. just FYI

MilesTeg

  • Pencil Stache
  • ****
  • Posts: 737
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #41 on: March 11, 2016, 04:18:50 PM »
Seafoam isn't going to fix a cat. The purpose of a catalytic converter is to burn unused fuel, and it uses platinum coated "honeycomb" structure similar to what you see in a radiator. The platinum is the catalyst for burning the unused fuel, and the honeycomb structure maximizes the surface area of available platinum.

The primary reason that a cat needs replaces is because the platinum coating and/or honeycomb structure has been damaged by excessive heat, rust or exhaust residue leaving less surface area/platinum exposed to catalyze the burning of unused fuel.

This is why it really is important to fix things like O2 sensors and other ignition components when the dummy light comes on (and not just ignore and/or reset it) because when those things are broken, the vehicle can "run rich" which means there's excessive unused fuel in the exhaust which the catalytic converter is there to mitigate, but just like any other mechanical component the more its used, the faster it gets worn out. The reason catalytic converters are really expensive is because they, unavoidably, use platinum as a catalyst, and platinum is an extremely expensive material.

Seamfoam only "cleans" the internals of the engine, and with modern vehicles is more of a hail mary than a real solution because, as others have pointed out, typically while cleaning the inside of the engine it breaks off chunks of gunk that clog smaller oil passages which will lead to complete engine failure.

If your cat is dead on a 7-8 year old vehicle that you put 2,000 miles on a year, it's either a faulty cat, faulty code, or you have a serious emissions problem -- probably due to improper maintenance. If you have an emissions issue, you have to tackle the source: Broken ignition/timing components or a sludged engine. If you don't fix those things, a new cat will be destroyed in short order.

There is no easy fix-in-a-can to a sludged engine (e.g. seafoam) causing emissions problems. You'll have to strip the engine apart and manually clean it (if the sludge is bad enough). Just like most things, an ounce of prevention is worth a pound of cure. Use the proper oil for your vehicle, and change it according the the manufacturer's schedule. Even if you only drive 2,000mi a year, you need to be changing your oil according the the maximum time interval specified in your car manual. Oil, once exposed to engines contaminants (especially gasoline), begins to break down and continues to break down if even you aren't driving the vehicle. And, there IS a significant difference between oils -- the cheapest stuff is fools gold.
« Last Edit: March 11, 2016, 04:36:59 PM by MilesTeg »

Duchess of Stratosphear

  • Bristles
  • ***
  • Posts: 326
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #42 on: March 14, 2016, 07:38:52 AM »
I've taken pretty good care of the car with regular oil changes and maintenance. So far the CEL hasn't come back on. MilesTeg, is there some way to determine exactly what about the cat turned the light on to begin with? The dealership just wanted to replace the whole thing, so clearly they aren't the ones to go to for help. Is there a test that would determine what's going on?

William Cannon

  • 5 O'Clock Shadow
  • *
  • Posts: 21
Re: Any hope of cheaply fixing my catalytic converter issue?
« Reply #43 on: March 14, 2016, 07:08:52 PM »
I had the same on a toyota with 130k mi.  I replaced the PCV valve ($5 and 30 min) and after 10k more miles the CEL has stayed off.  In my case, it appeared to be dirty burns due to a failing PCV valve.   I started with the cheapest option and started working my way up.


Like the other poster said, the cats could be fouled or you could have dirty burns, misfires, etc.  I suggest joining or even just searching  a forum for your vehicle.  That is where you will find the best advice.

Tapa