98 Accord: check enginge lite = cat out of spec code

My 98 Accord 4-cylinder w/98k miles has been running fine, but I've
had the check engine light come on, then go out after a couple of
trips, the come back on again. Had it checked out by my local trusted
(non Honda dealer) mechanic who checked the codes and said it
indicated the catalytic converter was out of spec; he recommended I
take to Honda and see what they had to say, but not to rush into an
expensive cat replacement before figuring out exactly what the problem
was.
Honda dealer: when he plugged in the diagnostic computer, the check
engine light went out (!), and he said there were no fault codes!!!.
He said if my previous mechanic said it was a cat code, they would
replace it to the tune of about $900. Ugh. Still runs fine. Drove
it off the lot without a new cat, and the light stayed out for a few
more months.
Check engine light back on... back to my trusty local mech. He
checked, said it was the same code, offered to reset it to zero. He
seemed pretty knowledgable:
He said the car's computer checks parameters during each trip (each
drive that exceeds about 45mph), and if it finds a fault two trips in
a row, it sets the computer's check engine light. Then, if two trips
in a row subsequently occur without the fault, the computer will reset
(turn off) the light, and delete the codes.
Sure thing.. the check engine light came back on two trips later,
and has been on ever since.
Questions:
(1) Am I hurting the car by driving it with this light on? It
drives just fine and I've noticed absolutely nothing wrong with the
engine performance, from start and idle through 85 mph.
(2) What else could this be besides the catalytic converter? My
limited research here indicates it could be the O2 sensors up- and
down- stream of the cat. I'd prefer to check out less expensive
options before plunking down the cash for a new cat.
I put a lot of higway miles on this car, and adhere strictly to the
maintenance schedule published by Honda, though I don't usually let
them do it.

 

My 99 Accord EX 4 cyl has 78000 miles (mostly highway driving as well).
The check engine light came on twice and went off on it's own once . I had
my mechanic check the code the 1st time at 61000 miles it stated a CAT
problem but it went out within 4 days of coming and before I could get it to
the Honda dealer. The 2nd time I was at driving from Colorado Springs to CA
and had 72000 miles. I was in Grants New Mexico at the time The nearest
Honda dealer in Scottsdale AZ. said it would be fine to continue to drive to
CA before having it looked at. Both times the code dump was for the CAT.
Luckily I was under the 80000 mile government warranty. I'm sorry to hear
than your code did not kick on before the 80000 miles. $900.00 was just
about the same quote they gave me had it not been under warranty. I did not
have them check any other options before they replaced the CAT. Once they
replaced the CAT my mileage went up by almost 50 miles per tank full of gas
(highway driving). I usually drive at 80 mph on the highway.

Good luck.

Rick

 

UPDATE... Check Engine light went out today! No maintenance
performed... I'll just wait until it comes on again I guess.

Unfortunately my Accord is over 98k miles so out of warranty on
emissions system.

I did the ign switch also under recall - mine was giving me problems
for a while.

Thanks for your help so far,

Busterh

 

You might want to recheck warrenty, mine was increase to 150K. If you go in
saying your out of warrenty that's what you get.

 

I am having the same problems with my 98 Honda accord with the cat.
What do you guys say to an after market cat for a muffler repair
store. I was quoted $765 from dealer and $165 for an after market one
from a reputable muffler store. The store owner said the only
difference is that the after market cat will be a little bit louder.
What should I go with?

Thanks in advance.

 

Ask the store if their cat will have identical fittings to the Honda one -
if they say they have "adapters" to make it fit - keep walking.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??