Hi All,

My daughter recently purchased a 2010 Honda CRV EX w/121K a few months ago. I replaced a leaking radiator, all the brakes and rotors and changed all the fluids. We know the car was well kept because she purchased from a relative who had good records.

A few weeks ago a P0302 engine code came on and the car stumbled a few times than ran fine. I thought it would be prudent to replace all the spark plugs and coil packs, My son-in-law did the labor. N codes the car ran great.

Yesterday a P0301 code went off. Being the parts were new I removed the plugs and coil packs to insure that they were installed properly. I found that the cylinder #1 plug was loose and when it was removed it was missing the "ground electrode" ??? My son-in-law could not be sure if the electrode was there when he installed it. It was 0 degrees in New York and he was working outside so I gave him a pass :-). I used a magnet in the cylinder to see if it was possibly there with no luck. A few calls to friends said if the piece broke off after it was installed could have left through the exhaust and might be in the catalytic converter.

Next chapter I installed a new #1 spark plug and checked the remaining 3 plugs and coil packs. I started the car and it ran fine. The P0301 code was gone but now I have a P0420 code which indicated an issue with the catalytic converter or a bad "Downstream Oxygen Sensor".

It can't be a coincidence that the Cat or oxygen sensor went bad after I changed the bad plug? If that "ground electrode" went into the cat could that be a possible cause?

I welcome any input!!!

Bob K

 

Clear the code and see if it returns. Misfires destroy the catalyst so you may need to replace the cat.

 

Do you think it's worth changing the downstream oxygen sensor first? I hate throwing parts at a car but it's relatively cheap and would rule that out. Also I was reading about Catalytic Convertor Cleaners that you add to gas. Do you think that's a waste of money?
Thanks,
Bob

 

No, If the sensor were bad if would be a different code.

 

Thanks

 

If the catalytic convertor is bad. I see many catalyric convertors listed on Rock Auto with price ranges from $200 to $1000! Any recommendations for a 2010 Honda CRV EX that will do the job without breaking the bank?

Bob

 

Reading between the lines I get the impression that you are using parts that may be counterfeit and now paying the price.

While the advice from @grcauto is good there are a couple of things I might try before firing the big canon again. First is to run a bottle of cataclean through the system per the instructions. Next is to clear the code(s) to see if they remain cleared. Lastly is to replace all 4 plugs with fresh NGK’s from a dealer or parts store.

 

Yesterday I did order "Cataclean" and am waiting for it to be delivered. I read that if high heat caused the damage in the catalytic convertor the cleaner is probably a waste of time.

A few weeks ago a P0302 code came on prompting me to buy NGK plugs and NGK coils from Rockauto. Since the car has 121K miles anyway it might be time.
My concern now is that the old misfire P0310 & P0302 codes are gone now but are replaced with a P0420 code. Hopefully the misfires before the parts were replaced didn't cause the catalytic convertor to get fried like "grcauto" suggested.

If the catalytic convertor needs replacing I was looking for suggestions on a good quality with reasonable priced replacement. Rockauto lists many types with varying prices. I live in New York so I know it has to be "CARB" certified meaning higher price range!

Bob

 

For a replacement Cat to pass NY emissions it would be California spec so you will need to know what “family” your V needs. Rock Auto should be able to help you with that if need be.

Sounds like you are headed in the right direction.

 

Appreciate the help and will report my progress!