RL1924

So this is a NON s2000 question but some of you seem to have an answer for everything... may not always be right but ....

Anyways my sister has a mazda tribute truck, About a week ago it stalled out on her and wouldn't start, turned out it was the cat it was clogged destroyed, so they had a guy down the shore replace it, being thats where she was when this all happend. Been driving fine same symptoms started happening again not being able to accelerate now 25mph and under, brought it to our local guy... The new cat is destroyed again. What could be destroying the cat like this?

Thanks in advance guys

My_Yella_s2k

o2 sensors can cause this to go bad, esp if its fully rich...
how is/was gas milage before this has happened?

bat cat from the get go...
any CEL's?
if so, it would be P0420 for the cat deterioration.

orangebarius

yup o2 sensors.

RL1924

No cel's which is an odd thing... When you say o2 sensors bad o2 sensors could cause the cat to be destroyed? The new ones only been in for about a week and she was told that one is now shot.. He wants to put a straight pipe in place of the cat so he can see whats going on since now he can hardly drive the car as is

My_Yella_s2k

bad o2 sensors can read false, either by "reading" to much air in the exhaust, or to much fuel, and sending a note to the ecu to drop or add fuel
with a bad primary o2 sensor, and a good secondary o2 sensor (which is usually in cat) it will call for the ecu to dump more fuel, sicne its only reading o2.
in doing so, the internals of the cat cannot breakdown fully the NoX / HC and the honeycombs will melt/breakdown and have HUUUUGE backpressure.

make any sense?
makes sense in my head, but may not of come out right...

RL1924

Ahhh does make sense gotcha now.. thanks

orangebarius

good stuff mike.

2ks2knyc

That truck is pretty much the same as the Explorer which is known to suffer from o2 sensor problems. I believe its a ford thing ..

When I was working at a Goodyear station, I would give the customer a heads up that it could be costly even before doing the work because we would end up replacing ALL the sensors in the long run and the issue would sometimes still bounce back. My advice .. change them ALL at once and see how that goes..

bungholio

didn't i tell you it was the O2? Now hand over your sister. Timmy Pastor style.

Pastor

Shhhhhhhh not everyone knows i give my sister away.