NEED HELP - OBDCODE P0420

[sriv1]

Hi Gurus,

Need your inputs. I have Honda Civic 98 model with 98K on it.

Recently, it popped check engine light, when i checked the code, it is P0420. I erased it and it didnt popup for a month. It came up again, and on getting it tested, the mechanic said Catalytic converter should be replaced and costs 650$.

 

Why is it didnt show up for a month when first time I erased? Any idea?

Is it worth replacing Catalytic converter on a 98 model? Because, I am sure i need to replace timing belt also very soon, so it adds up to cost of repair.

Third, mechanic said- even after replacing catalytic converter sometimes the check engine light comes up again. In that case, O2 sensors also should be replaced, which will further add to the cost.

 

Please assist me.

Thanks In Advance

[Kastigir]

P0420 could be the O2 sensor or the converter. Replace the cheapest part first. I'd replace the front O2 sensor. At 98k, you're about 8k over due on your timing belt.

[sriv1]

hey Kastigir,

 

Thanks for the suggestion, I think you are right. BTW, my car manual says timing belt change at 105K.

 

I couldn't confirm the replacement of Catalytic converter in time, so I had to take the car back in the evening. On my way back, to my surprise the check engine light went off. What could have happened, also car seems to be running smoothly. Is it possible, that while diagnosing the mechanic did something which caused the light to go off on its own? Really praying for it not to come back

 

 

 

Thanks alot.

[Kastigir]

hey Kastigir,

 

Thanks for the suggestion, I think you are right. BTW, my car manual says timing belt change at 105K.

 

I couldn't confirm the replacement of Catalytic converter in time, so I had to take the car back in the evening. On my way back, to my surprise the check engine light went off. What could have happened, also car seems to be running smoothly. Is it possible, that while diagnosing the mechanic did something which caused the light to go off on its own? Really praying for it not to come back

 

 

 

Thanks alot.

Pick up a #1 O2 sensor and replace it. 95% sure that's your trouble. Unless something has changed, Civic timing belt replacement is at 90k. Accord 4 cylinders are 105k.

[Tubbith]

Im havin the same issue with my 3.0CL at the moment. CEL came on, went away after a few hundered miles, and just came back on a few days ago. Im a poor bastard, so im just ridin on the CEL till i can replace the O2 and hope that was the issue.

[Kastigir]

Im havin the same issue with my 3.0CL at the moment. CEL came on, went away after a few hundered miles, and just came back on a few days ago. Im a poor bastard, so im just ridin on the CEL till i can replace the O2 and hope that was the issue.

Have you even pulled the CEL to find out what the problem is?

[sriv1]

OK, the CEL is back again.. So, there must be a real problem... Mechanic says its with catalytic converter per his diagnosis. Last year, I had the same problem P0420 and then it got fixed by replacing the o2 sensor. Again this year, this really sucks bleh

[Kastigir]

OK, the CEL is back again.. So, there must be a real problem... Mechanic says its with catalytic converter per his diagnosis. Last year, I had the same problem P0420 and then it got fixed by replacing the o2 sensor. Again this year, this really sucks bleh

Have you replaced the sensor yet?

[Tubbith]

Yeah i pulled it.. threw the 0420 code. Which from what i read online, could be anything from cracked EM to O2 to Cat Co. Im going to replace the O2 pretty soon. Hope thats it, cuz i gotta get new tags here shortly.