tune up/ mass air flow question

[bwood]

Something to add, cats don't just clog up all of the sudden and generally start to fail due to working harder than they're suppose to. Burning oil, running rich/lean, burning coolant all decrease the life of a converter. I can go right now to at least five of these trucks with 150k+ and still running fine on stock cats. Now that I have a circled the bush, here's my point, even if you remove the cats and program the rear O2s out, you may still have an underlying issue that did the cats in originally.

Here is some reading on catalytic converter operation:

http://www.aa1car.com/library/converter.htm

[spudz]

Originally Posted by bwood

Something to add, cats don't just clog up all of the sudden and generally start to fail due to working harder than they're suppose to. Burning oil, running rich/lean, burning coolant all decrease the life of a converter. I can go right now to at least five of these trucks with 150k+ and still running fine on stock cats. Now that I have a circled the bush, here's my point, even if you remove the cats and program the rear O2s out, you may still have an underlying issue that did the cats in originally.

Here is some reading on catalytic converter operation:

http://www.aa1car.com/library/converter.htm

True but not always. These trucks cats seem to come apart and clog themselves up sometimes. And the hwy patrol tahoe dog trucks I work on get cats all the time and the only explaination we can come up with is they idle them all day. But your right. If they are melted or clogged it is from an underlying issure.