brycecubes

My check engine light came on a few months back. It seemed to be that the gas cap wasnt on tight. Now my check engine light is back on , i went to Autozne and got the code, it is p0420. Most people say it is the catalytic converter. Since the check engine light has came back on, in the mornings when you try to start the car the first time it is like the battery is dead, the card doesnt attempt to turn over, and actually reset the time on my clock and cleared the check engine light for a little while. could a bad cat do that? Also i recently had my transmission fluid changed but that was after i got the check engine light.

poorman212

Check the cables, both and both ends to be sure they are clean and tight. Then if the issue is still there, have the battery tested.

Have the O2 sensors ever been changed or tested?

hondamark35

like poorman212 is implying, your list of symptoms are from more than one root issue. although it's good to check/test the O2 sensors 9 times out of 10 the fix is a new cat.

what the P0420 is telling you is that the cat. converter isn't cleaning the exhaust as well as the EPA would like it to. the way the PCM knows this is by comparing the outputs of the two O2 sensors, before and after the cat. so it's plausible that an incorrect/faulty reading from one of the O2s could make it "think" the cat is "below threshold" when it's really fine. uncommon, but possible.

the other problem(s) sound like loose or faulty wiring, specifically around the battery and/or fuse block.

brycecubes

thanks

brycecubes

so the issue when i was starting the car was with the battery, since i replaced the battery the check engine light is staying off. Have you ever heard of a low battery causing the P0420. Also when you remove the battery does that clear any codes that are stored or do you have to clear them someother way?

hondamark35

replacing/disconnecting the battery (for 10 sec.) clears the codes in the memory.

there is no relation one way or the other between the weak battery and the code. a weak battery will not create or induce a trouble code in the ECU. i wouldn't be surprised if the code comes up again in the next week or two. however, i would wait for it to come on again before taking any corrective action.

DCFIVER

Nawww, the code will return.

h0p3l355dork

Most likely it's the cat, I have a 99 accord as well and had to smog (Cali) so I had to bite the bullet and get a new cat. bought it from Majestic Honda for the low price about ~$500.. At least I'll be good for another 100K miles..

Mr. Bubble

Hey if u want I'll buy your bad cat on the car now and I'll give u a good price. Lmk shoot me a text. 9084871848