1998 Accord - P0420 - Cat?

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Almost 2 years ago, I gave a friend (single Mom) a 1998 Accord LX 4 banger with 85K miles that was in perfect condition.
My folks bought the Honda new; I am the only one who has worked on the car. Always garaged along with the low miles.
It now has maybe 120K and is throwing a P0420 trouble code. It also dies sporadically, but restarts easily.
Of course it would be nice if it were caused by a faulty O2 Sensor, but that's wishful thinking, right?

I understand that code is for the catalytic converter, which is big bucks thanks to our old Governator.
Anything to try first?
I appreciate your help. And if you know a good (aka cheap) muffler bearing shop in the West Sacremento (Woodland, CA) area, please chime in.
Thanks in advance.
 
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Checking for and fixing any exhaust leaks should be your first task. Then would be replacing the O2 sensor(s). After that, then it's probably the cat.

Looking at Rock Auto, the cat doesn't look like it would be too hard to replace yourself if necessary with just two flanges and six bolts, but there is certainly a price premium for the CARB models. Yikes.

How picky is CA regarding fixing emissions/exhausts on 23 year old cars?
 
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I second the recommendation to check for any exhaust leaks, my old LS400 was leaking from deteriorated gaskets around the 2nd cat.

Throwing code for cat below efficiency

sealed up with some versachem mufflerweld and was good for another 4yrs when I sold it.

For the dying sporadically I would try running a few bottles of techron through it mb
 
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P0420 is very generic when it comes to Hondas apparently. It can be a variety of things from O2 sensor to the catalytic converter. A technician can do more in-depth diagnostics to pinpoint a specific issue though.
 

JeffKeryk

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We got a referral to a muffler shop in Citrus Heights (near Sacremento). $720 and 45 minutes later, the little 4 banger is running like new.
I still don't understand on how a low mileage, almost always garaged cat goes in about 120K miles.
FYI, our famous Governator pushed through a law that required certification on catalytic converters that made cat replacement go from $90 to $700. Or more...
Oops. Today I will service the oil and replace the original rear brake linings. Easy peasy.
Thanks for all the replies.
 
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Fluke stuff happens. Sucks when it does. Cat may have died for no good reason.

$720 sure seems like a ripoff. At the same time it's what maybe 2 car payments? If the car needs nothing else for another year... yeah I wouldn't be impressed but at the same time it's "cheap" in the scheme of things.
 
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Lots of different things can cause a sporadic engine shut-off. Jumping to the conclusion that it’s a clogged cat can be a costly error (but I’m sure valve-stem mechanic guy would go that route) (lol that’s a joke).
OP, do you do any of your own work or do you definitely have to pay someone to fix it?
 
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Ignition switches were a big problem for them. If you ever have it stall out, don't touch the key until you look if the "oil" and "battery" lights have come on like they should when the key is on but the engine is not turning. If the switch cut out one or both of those lights will be out, and it will come back on when you jiggle the key..
 

JeffKeryk

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OP, do you do any of your own work or do you definitely have to pay someone to fix it?
I do as much as I can. And I have been at it for quite awhile. Sometimes I get in over my head.
My days of bench pressing a Turbo 400 into an old Firebird are over; that much is for sure.
The car threw a P0420 trouble code; in my experience that is a bad cat. No way around it.
I believe the old cat was pretty clogged; Cindy reports is is much stronger now. She pushed it to 100 as a test!
That little Honda 4 banger never went that fast before, I pretty sure of that.
I think the trouble codes were cleared; I will see if another come back.

The car still stalls out. Part of the problem is, my friend lives near Sacremento, about 130 miles from me.
I hope to figure out the stalling; then it's oil changes for years. Everything else is done.
I suspect the ignition switch, but who knows for sure.
I will try and get an accurate description of the shutting off and go from there.
 

JeffKeryk

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Fluke stuff happens. Sucks when it does. Cat may have died for no good reason.

$720 sure seems like a ripoff. At the same time it's what maybe 2 car payments? If the car needs nothing else for another year... yeah I wouldn't be impressed but at the same time it's "cheap" in the scheme of things.
$720 is a ripoff. Go to Rockauto or wherever and look up a cat for a 98 Accord LX 4 banger. You will see 2; one cheap enough and one crazy. Thanks to Gov. Swarzenneger. Some cars are far higher.

This is a perfect car for Cindy. Low insurance, registration, etc.
If I can get the stalling straightened out, all will be good.
My folks bought the car new; this never happened until a few months ago.
 
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$720 is a ripoff. Go to Rockauto or wherever and look up a cat for a 98 Accord LX 4 banger. You will see 2; one cheap enough and one crazy. Thanks to Gov. Swarzenneger. Some cars are far higher.

This is a perfect car for Cindy. Low insurance, registration, etc.
If I can get the stalling straightened out, all will be good.
My folks bought the car new; this never happened until a few months ago.
Rock Auto has CARB-legal cats for $400, so maybe they'd be $500-600 from a B&M with higher costs to account for. $100 or so for labor, and then tax, I could see $720

There are CARB-legal universal cats for the 1998 Accord 2.3, but they are almost the same price as the direct fit cats.


O2 sensor spacer would have been less than $10
and the fine would've been hundreds, at least :alien:
 

JeffKeryk

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Rock Auto has CARB-legal cats for $400, so maybe they'd be $500-600 from a B&M with higher costs to account for. $100 or so for labor, and then tax, I could see $720

There are CARB-legal universal cats for the 1998 Accord 2.3, but they are almost the same price as the direct fit cats.



and the fine would've been hundreds, at least :alien:
If you check RockAuto detail, the cheapest CA legal cat is $547 + tax + shipping. Others are $572 and $900.
CARB legal ain't enough.
Ouch.
 
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If you check RockAuto detail, the cheapest CA legal cat is $547 + tax + shipping. Others are $572 and $900.
CARB legal ain't enough.
Ouch.

What do you mean CARB legal ain't enough? CARB legal means it's legal for sale, installation, and use in California.

Walker #82996 and Eastern #630525 are around $400 each. Both are listed on California's list of approved aftermarket cats, and they even provide a link to the EO which approves them.
 
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