Cat converter light back on


Asked by Aug 21, 2016 at 02:57 PM about the 2007 Dodge Ram 1500 SLT Quad Cab 4WD

Question type: Maintenance & Repair

New cat converter system , 4 oxygen sensors new,
new canister.light came back on after 4 months
180,000 miles 2007 truck runs great .ac pulls
power when on
Trans,oil, radiator  flushed  what am i missing? 4.7
flex fuel engine.

11 Answers


What is the 4 digit code you are getting?

1 of 1 people found this helpful.

Bank 2


We need the trouble code. P0420, for example is a valid trouble code. It'll be a "P" followed by four digits. -Jim


P0441 incorrect purge flow

1 of 1 people found this helpful.

That has nothing to do with the catalytic converter or the oxygen sensors! This is a problem with the EVAP system. Most likely cause is a faulty purge valve. HTH. -Jim

1 of 1 people found this helpful.

Sorry that code was at 185,000 this is the latest one at 189, 000 P 0430 cat system efficiency below threshold (Bank 2)

1 of 1 people found this helpful.

Oh, ok. Did you check the emissions decal under the hood before replacing the converter the first time? If it says "conforms to California emissions standards" or "is C.A.R.B. compliant" you have California Emissions and a special catalytic converter is required. Even if you do not live in California you may still have California Emissions. My '03 S-10 Pick Up was originally delivered to Delaware and has California Emissions. So does my 2000 Grand Prix which was originally delivered to New Jersey. A Federal Emissions converter will not last for long on a California Emissions vehicle. You need a converter that is C.A.R.B. compliant if that's the case. HTH. -Jim


Okay I checked under the hood and this is what it read. This vehicle conforms to US EPA interm 2 bin 8 regulations applicable to flex fuel 2007 model year new light-duty trucks and meets us EPA clean fuel fleet lev vehicle regulations this vehicle is certified to operate on unleaded gasoline or an unleaded gasoline / ethanol blend containing up to a maximum of 85% ethanol

1 of 1 people found this helpful.

Ok, good. Sounds like you don't have California Emissions. When buying the new converter, tell the parts person or service writer that information. There are a few things you should know to prevent this kind of premature failure again. First, bank 2 is the side of your engine that cylinder number 2 is on. So whichever side that is (driver's side or passenger's side) that's the converter that's throwing the code and needs to be replaced. Second, I always recommend Eastern Converter. They have a very informative website including videos! Before I went to work for NAPA I worked at another auto parts store chain for about 5 years until they went bankrupt. All we sold were Eastern Catalytic Converters. I honestly don't remember any coming back defective! They're an excellent converter. I've had an Eastern converter on my '03 S-10 Pick Up since 2011 and one on my 2000 Grand Prix since 2013. No issues with either one to date. Third, a brand new, never used, catalytic converter has to be warmed up before it's placed into service. This is done by holding the engine at a fast idle for several minutes once the converter is installed on the vehicle. This melts the catalyst (honeycomb, or brick as it's sometimes referred to) into place. Without doing that the "brick" will be damaged as soon as you drive the vehicle for the first time after the installation. This will greatly reduce the service life of the converter. Eastern Converter has a video on their website that explains this in more detail with pictures. Lastly, most catalytic converter failures are caused by engine trouble. Misfiring, burning oil, and coolant leaking internally are the 3 most common causes of converter failure. So make sure you have no issues with the engine before replacing the catalytic converter! There are other causes of converter failure such as thermal shock. But these instances are rare. Thermal shock happens when you drive through freezing cold water and the converter, which is about 500°F gets soaked with the freezing cold water. It can happen, but it's rare. Check out those videos on Eastern's website. HTH. -Jim

2 of 2 people found this helpful.


1 of 1 people found this helpful.

You're welcome. Glad to help. -Jim

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