Ck engine light cat converter


#1

I have a 1996 toyota corrola 146.000 mi 1.6 engine my ck engine light came on and i had it cked and it read catalitic converter bad had it clicked off it came back on a bout two months later same results Ive been told that the readiny dos not always mean cat converter but could be oxigon sensers is this correct?also a local muffler shop with a good reputation said the would install one with a 5yr or 50.000mi warrenty but it is a weld on iv heard that some muffler shops put any ol generic cat conv on and to be carefull of this the price is about one third of the Toyota dealers price p.s. this is a california car thanks ever one I not sure what to do


#2

That is correct, it could be the oxygen sensor.

Having said that, it’s not uncommon for a marginal cat converter to begin to manifest itself as an intermittant Check Engine Light. And I’ve recently become aware that it’s a common problem in Toyotas at about 150,000 miles. Until '96 when OBD II systems became mandated, converters weren’t monitored for efficiency, so unless it rotted out or crumbled inside converters were forever, but it seems that current standards have made the Toyota cat converters become marginal at about that mileage.


#3

There is no code that says the cat is bad! There is a code that says something like “catalytic converter below threshold,” but that does not necessarily mean the cat itself is bad, or needs to be replaced.

Failing O2 sensors will often trigger this code. Try new O2 sensors before you spend the money for a new cat.


#4

A new rear sensor cured my problems…


#5

A few weeks ago, on a long downhill run going over the mountains in Mexico, I go the 0420 code, cat converter below threshhold. This week the light went out again, we are betting it comes back soon. My Sienna has 175,000 miles on it.