Who has changed the cat on the manifold?

[Tifun]

car is an 02 early build date. Trying to figure out if there really is a difference between early build dates and late dates. Is it the same as the regular protege as well???? Any help or links to clear this up or someone want to see me their used one????

[slavrenz]

The manifold cat is the same part for all 2001 - 2003 Mazda Protege's and Protege5's. If you want a quality replacement that isn't nearly as expensive as the OEM cat, check out this link:

http://www.rockauto.com/catalog/raframecatalog.php?carcode=1387447&parttype=5808

You want the Walker #16220, which carries a 5-year, 25,000 mile waranty.

[Tifun]

Hmmm. The two books I went through showed there was an early build date protege5 with a different system as well as the dealer who showed two different part numbers for the same year. I assume then that the different part is the system after the cat then maybe? ANy verification? I really don't want to buy a part twice so I'm looking for more than just "yeah it will work" lol.

[slavrenz]

The part number for all Protege's sedans (with the 2.0L engine) & Protege5's (which all have a 2.0L engine) is:

FS7N-20-50XA

I can 100% guarantee you that there is only 1 part. Whichever dealers told you that there were two are high.

They may be mixing up the Protege5 with the Protege sedan. The 3rd gen sedan was made beginning in '99 and until '01 had a 1.6L engine. In 2001 they made sedans with the 1.6L and 2.0L engines, and then from '01-'03, every Protege and its variants (Protege5, Protege MP3, Mazdaspeed Protege, etc.) had a 2.0L engine.

[slavrenz]

The part number for all Protege's sedans (with the 2.0L engine) & Protege5's (which all have a 2.0L engine) is:

FS7N-20-50XA

I can 100% guarantee you that there is only 1 part. Whichever dealers told you that there were two are high.

They may be mixing up the Protege5 with the Protege sedan. The 3rd gen sedan was made beginning in '99 and until '01 had a 1.6L engine. In 2001 they made sedans with the 1.6L and 2.0L engines, and then from '01-'03, every Protege and its variants (Protege5, Protege MP3, Mazdaspeed Protege, etc.) had a 2.0L engine.

[Tifun]

Awesome, thanks.

[slavrenz]

Hmmm. The two books I went through showed there was an early build date protege5 with a different system as well as the dealer who showed two different part numbers for the same year. I assume then that the different part is the system after the cat then maybe? ANy verification? I really don't want to buy a part twice so I'm looking for more than just "yeah it will work" lol.

Oh, I know what you're talking about. Halfway through 2002, they switched the part number of the catalytic converter underneath the car. This doesn't have anything to do with the converter near the manifold, however (our cars have 2 cats, but only the one near the exhaust manifold is monitored by the ECU).

[Tifun]

I think the ECU reads the rear one at some point. It was replaced at the dealer under that cat law they have about 2 years ago just before we hit 100k. It ran perfect until recently. However....after rooting around in the engine bay again, it looks like my newishly used intake boot has another dry rot crack in it. Last time I got that code for the same crap and figured I was good this time until I took it off to find dry rot at the throttle body. I need to just buy a good CAI now to replace the entire air box system that obviously fails.

[Bret2002]

i would suggest getting a short ram for sure. especially having lived in valpraiso and knowing how shitty the winters are. its prolly all that salt and slush eating through that rubber hahaha. god bless lake effect snow

[slavrenz]

I think the ECU reads the rear one at some point. It was replaced at the dealer under that cat law they have about 2 years ago just before we hit 100k. It ran perfect until recently. However....after rooting around in the engine bay again, it looks like my newishly used intake boot has another dry rot crack in it. Last time I got that code for the same crap and figured I was good this time until I took it off to find dry rot at the throttle body. I need to just buy a good CAI now to replace the entire air box system that obviously fails.

It is not possible for the ECU to monitor the rear cat, since there is no oxygen sensor on the downstream portion of the cat. In the manifold cat, the ECU compares the voltage readings of the O2 sensors before and after the cat, and makes sure that the rear sensor voltage fluctuates a lot slower than the front sensor voltage (basically, this means the cat is doing its job of removing NOx, carbon monoxide, and hydrocarbons).

Consider yourself lucky that you got your cat replaced under that emissions law- dealers only have to warrant it out to 80,000 miles. As for your intake, never get a used boot. They're bad enough from the start for our cars, but like you said, just slap a CAI on there and you're good to go ;)

[Tifun]

I ended up finding a new tube at the dealership. I figure the next time around will be in the new owners hands. I still have to get the cat. I also read quite a few reviews/complaints about CAI's causing hesitations. I'm in shopping mode right now. I have a few friends who can usually get me good prices and I'm waiting to hear back from them on this issue. Also if the law says 80k then it may have been longer than 2 years now. Also....from what you describe I doubt the ecu would throw a code showing the rear cat is bad, so I assume that it was indeed the front one that was replaced. I wonder why this car seems to eat cats...and rusts lol.

[slavrenz]

I ended up finding a new tube at the dealership. I figure the next time around will be in the new owners hands. I still have to get the cat. I also read quite a few reviews/complaints about CAI's causing hesitations. I'm in shopping mode right now. I have a few friends who can usually get me good prices and I'm waiting to hear back from them on this issue. Also if the law says 80k then it may have been longer than 2 years now. Also....from what you describe I doubt the ecu would throw a code showing the rear cat is bad, so I assume that it was indeed the front one that was replaced. I wonder why this car seems to eat cats...and rusts lol.

I've never seen cats more sensitive than the ones on our cars. A year and a half ago, I had a misfire that lasted for a total of one block (I was only one block from my house when that happened). Even that caused my cat to go bad, but my wife's sister, who's car has been misfiring for over a year, has yet to see the code for a bad cat even once.