What magnaflow converter do I need?

I just replaced my cats at a local muffler shop on My 2001 tacoma 3.4 liter, I am not sure the brand that was used but my cel is Still showing the code p0420 for my cats. This truck runs off of California emissions standard and The muffler shop techs are puzzled as to why the cel is still showing up. If I can have them replace the cats with a set of magnaflow, do I need to get a set that is 50 state legal OR a set that is 49 state legal but OEM grade? Also if the ones they have already put on are just standard universal converters that would be the reason the cel is still throwing that code?

 

Might be one of the gaskets on your O2 sensors. My 1996 had a leaky gasket and threw the same P0420 code. If you're not sure, replace them all and cinch everything down tight. The slightest air leak throws them out of range.


Greg

Oh, and did they disconnect the negative battery cable to make the ECU could go dumb so that it could relearn the new operating parameters?

 

No I do not think they disconnected the battery. Do I need to do that?

 

Hell yes!

Anytime you do anything that changes the operating parameters of your engine you should do a battery disconnect. And even if you fix the problem, the P0420 code will still remain until it's erased by a code reader or a battery disconnect.

Just do it yourself. Remove the negative terminal for about 15 minutes to be certain the ECU forgets all of its previously learned settings. Then simply reconnect the terminal and drive. First thing you'll notice is that the check engine light is out. While it's running the ECU will relearn the new operating parameters. If anything is still not right, it will take a while (usually about 5 cold start cycles) before any pending codes show up as permanent codes.

Try it just to see what happens... you won't hurt anything.


Greg

 

Thanks! I'll try that.
Also, if they did not equip my truck with a 50 state legal converter can that cause my light to stay on considering the emissions on my old cat would have been a lot stricter than a 49 state converter they put on it?

 

In my opinion, no. But try the disconnect first, then you can go from there.

A really useful accessory you might consider getting is your own OBDII code reader. I got a nice one for about $50 off ebay. They will tell you exactly what's going on with your truck in real time.


Greg

 

Do you know if an oxygen sensor would cause a code p0420? And how can I check for a bad o2 sensor?

 

Yes it can. And I believe that there's a way to test them but I don't know what it is. You can do a forum search for the topic. I'm sure people here have tested them.


Greg