Catalytic converter issues

[lou4902]

Hello,

My check engine light came on last September. I took it to a couple of auto parts stores and got the same reply -exhaust/catalytic converter or oxygen sensor issue.

I found it hard to believe since the vehicle only had roughly 50000 miles on it, but I took it to my local mechanic and had it replaced. The vehicle is running fine, but that check engine light keeps coming back on. My mechanic has checked and rechecked everything and nothing seems to be wrong.

Does anyone have any advice/input on what the issue could be?

Many Thanks

 

[ThatsNotABuick!]

What year and how many miles on your Encore? It might be covered under powertrain warranty. If not, then it might be covered under emissions warranty.

 

[DocBrown]

Also, what is the CEL code? And what was checked/rechecked?

 

[jjrichard4545]

Hello,

My check engine light came on last September. I took it to a couple of auto parts stores and got the same reply -exhaust/catalytic converter or oxygen sensor issue.

I found it hard to believe since the vehicle only had roughly 50000 miles on it, but I took it to my local mechanic and had it replaced. The vehicle is running fine, but that check engine light keeps coming back on. My mechanic has checked and rechecked everything and nothing seems to be wrong.

Does anyone have any advice/input on what the issue could be?

Many Thanks

I have the same issue with my 2012 regal 2.0 . Just replaced cat and getting code p0420

 

[YeahYeah]

When I asked my mechanic about a new catalytic converter for my 2016 Encore he told me that there's two types of catalytic converter available: an aftermarket one and an original OEM from the dealer. Or course the aftermarket one is half the price, but, he said in about 3-6 months the CEL will come back on.

 

[02LTD2.0]

.....as long as the converter is not clogged you could use an O2 extender to "trick" the ECM into seeing appropriate behavior from the downstream O2 sensor.

 

[century61]

.....as long as the converter is not clogged you could use an O2 extender to "trick" the ECM into seeing appropriate behavior from the downstream O2 sensor.

I had to do that on my GF's 2007 Lucerne. The dreaded P0420. From what I understand, The OEM is the California standard and the cars are tuned to that. So, The less expensive cat will not work. Of course if the old cat is clogged then you could go the less expensive one and just install the O2 extender 😉.

I have watched some videos where people just took a pipe or old bat and rammed it thru the old cat to clear it out and then put it back in place with the extender. 🙂

 

[02LTD2.0]

Desperate times call for desperate measures.😉

 

[prohidium]

I had a cat issue on my 2014 Encore and I did a cat clean and it improved the situation but in the end it appeared it was actually an issue with the spark plugs. The issue initially cropped up as poor acceleration one day and then a few days later the dreaded cat error code. Thinking it was a clogged cat, I bought some Duralube cat cleaner. It worked for a short period and then the cat error code came back ( P0420 I think ). I did a second cat clean and it cleared again. About 2 weeks later the check engine light came on again and I was still having some sluggish accel from time to time. I didn't think it was a clogged cat myself so I started thinking about a bad spark plug and I read that bad plugs can mimic and cause cat errors. I replaced the plugs and everything has been running fine since (over 3500 miles ago). Plug replacement was fairly easy but just have to be careful lifting off the coil pack so as not to tear the boots. This all started happening at just over 55k miles and I always assume the plugs were easily good for 100k miles. Not always the case! I figure the cat clean temporarily improved the spark for a short period of time vs. actually cleaning the cat.

 

[02LTD2.0]

Do a Google search for Big Daddies Garage.