CHECK ENGINE LIGHT

the check engine light keeps coming on, the scan tool reads p0432, which is main catalyst below effeciency bank 2. Is there any whay to check the (4) 02 sensors without replacing them all? could this be a problem with the cat? if so is there any way to check that?

if it was an individual o2 sensor it should spit out a code saying that specifically. otherwise I would start by cleaning the o2s and inspecting the cats

How many miles on your cat converter? The fact that your OBD system is detecting catalyst efficiency low on bank 2 to me would mean that it would specifically be the "downstream" bank 2 O2 sensor being suspect as the downstream sensors are the ones that primarily check efficiency of the catalytic converter. They can be tested with a good meter or an o-scope if you want before replacing. I'd start by checking out that specific sensor if it were mine; this sounds to me like that particular sensor may have gotten "lazy" with age.

If you find or decide that you do need to replace, spend the money and get good quality OEM style sensors. Stay away from generic crap and cheap e-bay stuff; there is a LOT of junk out there! Good Luck!

I would run a couple of bottles of Chevron Techron Fuel system cleaner, I've used it for years since I got my 98 in Dec of 97. I still have my original OEM sensors and cats. I would also take it out and blow the snot out of the engine if you do mostly around town local driving. A couple of hundred miles may clean a lot of crap out and keep the RPM's high. At that point you might also want to use a good decarbonizer, GM Top Engine cleaner for one, Chrysler also makes a spray type that the techs I have talked to at the local dealer like quite a bit, then there is a good decarbonizing with seafoam.

This is where I purchased the O2 sensor for my '98.


http://www.autopartswarehouse.com/search/?N=10854+1557+4294965604+9166+802&V=10854+1557+4294965604&Vh=1998%20Jeep%20Cherokee