Honda failed CA emissions... any advice?

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Originally Posted By: LeakySeals
If you can get the cat off they can be cleaned...


I wonder if a water decarb might help clean the cat enough to pass inspection.
 
Originally Posted By: teambeechstreet
Originally Posted By: Scott_Tucker
Looks like it's going to be mostly cat that fixes it. CO and HC will definitely be cleaned up. NOx should clean up with a cat too but it may be close. You say it has no EGR, but it shows the EGR functional test as pass, not N/A. Are you sure it has no EGR?

The results are on the left side, which shows N/A for both Visual EGR and Functional EGR. Only the automatic transmission models had EGR


Lol, sorry I was so tired I read it wrong.
 
I am assuming you had the car really hot for the test otherwise you would get bad numbers. If you are waiting in line, keep the engine running.

But the numbers do signify a dead cat. Didn't the car gave you P0420 about five years ago? :)

- Vikas
 
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Originally Posted By: sunfire
Originally Posted By: LeakySeals
If you can get the cat off they can be cleaned...


I wonder if a water decarb might help clean the cat enough to pass inspection.


Laundry detergent and a pressure rinse. Comes right off
 
How much money is the car worth?

You want it properly fixed or to just pass and keep it on the road until the next smog check?

Properly I'd look at doing at least the head if not a bottom end rebuild, along with a new cat.

If your hard up:
M313.jpg
 
Originally Posted By: teambeechstreet
Originally Posted By: LeakySeals
Originally Posted By: teambeechstreet
I did a seafoam treatment through a vacuum line and tons of white smoke has been dumping out the rear. Haven't had a proper chance to drive the car to clear out the seafoam yet because I am at work.


Big mistake, seafoam is a cat killer, the worst thing you can use. The white cloud is pale oil which further contaminated your sensors and cat.

I'm going to replace the cat so I figured some seafoam before replacing the cat is no big deal.


eBay...search: "36635 magnaflow" $218 shipped. Direct fit, CA certified.
 
new cat = 200
new used engine: 200-400 new used engine

if you're capable of doing an engine swap, swap in a new engine.
 
Originally Posted By: hattaresguy
How much money is the car worth?

You want it properly fixed or to just pass and keep it on the road until the next smog check?

Properly I'd look at doing at least the head if not a bottom end rebuild, along with a new cat.

If your hard up:
M313.jpg





wow never heard of that... did some googling and apparently it works well. I would have tried that if I would have known about it before putting a new cat in our deviile.
 
Isporopyl will reduce combustion temperatures, helping the NOx, but likely making the HC worse.

I didnt realize that so many people had a halogen chemistry lab in their garage to "clean" PM-based items.

Actually a reduction in Hydrogen at temperature (very dangerous) might work.
 
My trick was to blend a couple gallons or so of E85 with 87 gas, this worked well for reducing all my numbers at 15 and 25 mph. Don't use too much E85 otherwise you'll have trouble starting the engine. I started noticing starting and running issues when I blended at pretty much a 50% rate. This was all on my now retired 94 civic which had a 1.5L jdm motor in it.
 
Thanks for all the tips and opinions! I replaced the cat ($180 installed) and took it back for a pre-test. Nox numbers are now within spec, but HC got worse and CO stayed the same. I'm currently looking into swapping in a used lower mileage engine or trying the denatured alcohol / E85 trick that I've been reading about. I've tried the "Guaranteed to Pass" stuff before in a different vehicle and it didn't work. I'm keeping my fingers crossed. This car has served me well and I'd like to keep her on the road.
 
Bad HC/CO says your car is not in tune i.e. the air/fuel ratio is not right. If all the tune-up parts are new, all the sensors are functioning and there are no leaks, I am out of ideas!
 
Update:

Per the advice of a smog tech, I replaced the coolant temp sensor and patched a tiny vacuum leak @ the throttle body. Got the cat really really hot and had it tested again. Passes no problem @ 15mph. At 25mph NOX is below average, CO is below average, but HC barely goes over MAX (MAX is 74 and I got a 79). With an almost empty tank of gas, I dumped in two quarts of denatured alcohol and had it tested again. Results were AWFUL!!! The HCs jumped up to 250, NOX to 600 (from 150), and CO went up to .70 (from .10). The smog guy called me stupid for even trying the denatured alcohol trick. He advised me filling up with 87, dumping in a bottle of Amsoil Fuel Performance Improver, driving it to empty, then filling it back up with 87 and getting it tested again.

This is driving me bonkers...
 
Originally Posted By: Chris142
Change the oil and put new NGK plugs in it. Often if you change out dirty oil the HC will drop 20ppm or so. I can't explain why but it does.


Thanks, but I changed the plugs two days ago with the correct NGKs. Oil & filter are only two weeks old.
 
Techron Concentrated Fuel System cleaner. Do two treatments as directed in instructions.

Also have you changed the air filter, and replaced the distributor cap and rotor, also make sure to clean out any oil residue from the throttle body and air intake snorkel,

ONE MORE THING.... ARE THE EGR port passages plugged?
 
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