My mechanic friend thinks my cat is going, tha he can smell it sometimes. How can I tell for sure, how hard is it to replace, and should I use an OEM or aftermarket cat? Thanks guys!

By the way, installed my Brembo blanks and Hawk HPS pads up front... very happy...

 

Give your cat a bath and brush her afterwards...should get rid of the smell and keep her purring. Course...the fur may get on your seats.

If that doesn't work, try running some catalyst cleaner through your system. Just because it smells...doesn't mean it's bad. Your mixture could be off.

These cars should be giving you a code if a serious problem exists. A clogged converter will sound like a vaccuum cleaner at the exhaust and reduce your mileage and power.

thanks!@

 

hmm. lately im getting only 200-230 miles per tank. and once in a while P0430 cat efficiency below threshold or something like that...
is it my cat. ? or maybe o2 sensor?
how can i tell for sure if my cat is bad. i don't want to spend x hundered dollars if i don't have to

 

Seeing as how I'm currently in the market for a used maxima and don't own one, I can't tell you for sure if this test is do able on your vehicle. But what the hay- I'll throw it out there anyways.
IF these cars have o2 sensor's. 1 before and one after the cat - you can do this test.

Simply warm the car until you reach closed loop status. (The pcm uses 02 readings as an input for a/f ratio, etc)
Take a voltmeter (Or multimeter set to volts) and backprobe your lead to the back of the sensor. (o2 will probably have 2 or 3 wires possibly 4 or 5, one is a ground, one is to heat the 02 sensor to get it to start operating sooner,if applicable, and the other sends the output signal.--input to pcm) Back probe the one that gives an output. Ground your other lead wire to a good chassis ground. (although rare, Alot of resistance can throw your readings off if grounding thru the engine). Both 02 readings should fluctuate similairly, going from around .01 to around 1.1 volts constantly very quickly. (A cheap multimeter may not even work for this.) If the rear 02 (After cat) has a higher average reading more than likely you have a bad cat and this would more than likely set off your MIL light. ----I think you can use a frequency counter for this as well, but forgot how to because we usually use a scope anyways. Good Luck--Hope this helps. sorry if this doesn't pertain to your vehicle.