98 Accord Catalytic Converter Crapped-Out!!!

For the last three years the catalytic converter on my 98 accord has
been bad according to my dealership. I had them check my car out after
the "engine" light came on. They said it was my cat and it should be
replaced, although I was 9k over the 80k warranty so I opted to not to
replace it. Two days ago a loud rattling noise started to come from
what appears to be the cat. I took the shield off and reattached it in
hopes that the shield was loose. The rattling is inconsistent, i.e. no
particular rpm. I live in a state that doesn't test emissions. I had
it tested and got three codes, one was P0420 and I got two for P1457
(which some people have said that's a leak in the evap control
system). What does that all mean? Would it be possible for me to
replace the cat with a straight pipe? Other than the obvious
law-breaking, what other risks do I run, such as what do I do with the
oxygen sensor and how will it affect my car over the long run? Do I
unplug it or attach it to the straight pipe? And finally, doesn't
the o2s work together with the injectors for proper performance?

Thanks for any help concerning this issue, Zeke

 

wrote in

There are a *lot* of heat shields. Check them ALL. If you find one corroded
and loose, a big hose clamp will quiet it down.

Lucky bastard. My province is highly Communist in its social-engineering
zeal. We have an extremely stifling smog check. They're using it to chase
old cars off the road and make us all buy hybrids with sixteen airbags.

Oh, and our province's Premier (Governor)? He looks just like
Lee Harvey Oswald! (Google for "Dalton McGuinty".)

Catalyst efficiency below threshold.

It is. It's the canister side, not involving the gas tank or gas cap.

Other than legality issues and your P0420, replacing the cat with a
straight pipe will do no harm of any kind. A straight pipe might result in
a little more exhaust noise than you're used to, but not likely more power.

Even with a straight pipe you will always face the MIL illuminating with a
P0420 code. The ECM tests cat efficiency at least once per trip, using the
secondary HO2S to do it. If it fails to see the correct response from the
sec HO2S to its efforts, it will keep setting the P0420 code. If you don't
mind getting sunburn from the MIL, and don't mind checking regularly to
make sure it's only crying "P0420", you could just...live with it.

Don't ya love OBD-II? Another reason I want to keep my '91 'Teg as long as
I can. My mechanic thinks I'm nuts.

 

I always refer to him as "Dumbass McGoofy".

For similar reasons, I'm keeping my '93 Accord as long as possible as well.
The overuse of electronics in many new cars greatly concerns me.

 

Tegger, what would be involved in checking for and possibly fixing the
leak, I'm NOT car savvy and would like to fix this issue on the
cheapeast. What is this canister I keep reading about. By the way,
tell the women and children to run for the hills, Dalton McGuinty is on
the loose. Creepy-looking-cat.

Thanks, Zeke

 

Tegger, what would be involved in checking for and possibly fixing the
leak, I'm NOT car savvy and would like to fix this issue on the
cheapeast. What is this canister I keep reading about. By the way,
tell the women and children to run for the hills, Dalton McGuinty is on
the loose. Creepy-looking-cat.

Thanks, Zeke

 

Sorry that goes out to HTM as well!!!

 

Ah, a kindred soul! You didn't vote for him either, right?
If only Eves hadn't been such an idiot...

As you well know, it's ALL driven by environmentally-based legislation and
regulation.

 

wrote in

You can't do it yourself. Unfortunately, it's highly likely you'll have to
get a new cat installed by Midas, Meineke or other place. Their cats will
be good for at least a couple of years, and even with multiple replacements
will still be cheaper than new OEM.

Having said that, there has been the odd report of cracked exhaust
manifolds that have admitted inappropriate oxygen to the exhaust after the
first sensor, so you might want to get that checked. The cracks are around
the sensor hole, according to the reports I've read.

The "canister" has to do with evaporation from the gas tank. Since the '70s
cars have had charcoal-filled canisters to capture gas tank evaporations.
For the 1996 model year, the federal EPA mandated that the canister and its
associated control hardware should be made considerably more efficient and
sensitive. This means that minor errors that would have gone unnoticed
prior to 1996 will now turn on your MIL and make you spend your money to
turn it off again.

And just so everyone knows the scale of this sort of thing:
1) Emissions-wise, North American market cars have been CLEANER than the
ambient air (for measured pollutants) since the late '80s and continue to
be so. This is how the federal EPA can claim that the air is 57% cleaner
that it was in 1970, in spite of a 153% increase in vehicular traffic.
2) A pint of gasoline poured on the ground will emit more hydrocarbons than
a new car will emit (in total!) in 100,000 miles of driving.

Measured and regulated numbers in question today are impossibly tiny, and
yet the various regulatory bodies act as though it were still 1951. About
90% of vehicle emissions reductions were achieved by the mid-'80s.

 

I was inspecting my exhaust manifold after I received P0420 and P1457
codes on my 98 Accord. One of the nuts is missing and the bolt has
been sheared-off from one of the connecting points between my manifold
and engine. All others seem to be in fine shape. could this be the
cause of my problems, and how can the problem be resolved?

Thanks in advance, Zeke

 

wrote in

Could be. Sheared exhaust manifold studs will run the risk of air leaks.

Replace the studs.

 

didnt honda get in trouble for "dialing down" the sensitivity of their
evap control systems?

oh, ive seen the pictures of 60s/70s era los angeles, and the smog was
BAD back then.

and i think they oughta let things slide for a while, personally. at
least on the automotive front. go after the power generators, railways,
and big rigs.