2002 CR-V P0420 Code Question

[tedj1957]

I've got a 2002 CR-V LX with 127,000 miles on it. About 14 months ago my check engine light came on with P1298 and P0420 errors. I replaced the O2 sensor which fixed it for awhile then they both came back on. I had them reset several times and noticed that they only came on after a heavy rainstorm. The dealership did something with the computer board that they said might be causing it to throw bad codes, but the codes came back anyway. Then one day the code came on while I was on the road and before I could get back to town the code disappeared. The status remained for almost a year when it came back on with the same codes...after a heavy rainstorm again. Again the codes disappeared after a day or so. Then they came back but only the P0420 code. I've reset it a couple of times but it always came back. Then on Saturday morning it came back on...then later that afternoon it went off again. Oh, and this time it hasn't rained in 5 days. Any ideas?

[roadster]

P1298 wil be permanant code. and will be a ELD code main board. the otehr you may need to stand your ground for a repair if shop refused to fix. I have had that code since day one. some claim better proformance after a fix. I say whatever. never bothered me.

['Curly Q Links']

Originally Posted by tedj1957

I've got a 2002 CR-V LX with 127,000 miles on it. About 14 months ago my check engine light came on with P1298 and P0420 errors. I replaced the O2 sensor which fixed it for awhile .....

You saying you replaced the secondary O2 sensor or the primary ?

You need to get the temperature of your cat tested before throwing ANY more parts at your problem.

SEARCH: 'temperature sensor catalytic' to find out how to diagnose your problem from the correct end of the horse.

[tedj1957]

The primary O2 Sensor was replaced. It's down to just the P0420 code now. The code will pop up, stay on for about 25-100 miles and then disappear for anywhere from 200 to 1,200 miles. I am currently at 800 miles on the current run. (I use the 2nd trip odometer for this and record them in my car log book). The code can come on either when I am driving or when I start up the car...however it appears to always go off when I am driving.

[roadster]

thoseare the normal signs of the cpu memory board. a reminder. to get it checked. we keep ignoring and other codes will follow

['Curly Q Links']

99% it's either the cat or the secondary O2 sensor. One costs under $100, the other is about $800 if you want OEM, so spend $30 on an infrared thermometer and solve your problem.

See previous answers. Do the indicated search.

Read this page about the older HONDA ECU's (computer)


Since rainstorms are chilling the cat, it could be the cat or the sensor detecting lowered efficiency.

Do you make a lot of short trips?