NismoGizmo

@onespiritbrain Thanks for bringing up the under-hood Vehicle Emission Control Information. Unfortunately, Nissan changed the emissions setup between your year and 2003. I think the inspector I spoke with today said that the 2002 had 4 catalytic converters, but in 2003, there's only supposed to be 2. Here's the label from under my hood. I believe it is saying there are 2 Three Way Catalysts and that's it.

Well, bad news. The inspector said that I definitely *do* have catalytic converters which have been added to the "front tube" indicated by part number 2 on page 10 in the 2003 Pathfinder FSM: https://www.nicoclub.com/FSM/Pathfinder/2003_Pathfinder/fe.pdf I believe these "front tubes" also are the part indicated by 12 and described as resonators on this page: https://www.factorynissanparts.net/auto-parts/2003/nissan/pathfinder/le-trim/3-5l-v6-gas-engine/exhaust-system-cat/exhaust-components-scat The inspector even read off a part number, 445005 on it, which corresponds to a Magnaflow catalytic converter: https://www.amazon.com/MagnaFlow-445005-Universal-Catalytic-Converter/dp/B00AURR8SK So, *somehow* these catalytic converters are beneath my passenger compartment. I suspect that my friend had his "muffler" replaced, but actually had the resonators (which are mufflers) replaced. But the people replacing the resonators somehow replaced them with these Magnaflow catalytic converters instead of resonators. They likely did so since the resonators look very much like catalytic converters so they thought they were replacing catalytic converters. At this point, I am planning to go to an exhaust shop, cut off the extra catalytic converters, and have resonators or straight pipe welded in their place. I could try and go back to the place where my friend got his exhaust done and demand they fix their mistake, but he said it was done a long time ago (God only knows how he got it to pass smog all these years...) and it's likely under no warranty now. So, is there any advice on how to proceed? I've gone to one exhaust place already. They confirmed what is under my car are catalytic converters, and they've quoted me $300 to replace both of them with resonators and $200 to replace them with straight pipe. I'm going to get another quote from another guy tomorrow morning. 1. Does it make sense to buy straight pipe or resonators myself and provide them for the job so that I only pay for labor? 2. Is it possible to do this job myself? It sounds straight-forward: cut out the existing component, cut pipes that fit, and weld them in. How feasible is this for someone who has never welded? I am also considering a last ditch effort of going to the original dealer where my friend bought the Pathfinder and asking them if it was sold with these components in place. I'll probably be told the same information: that these are aftermarket catalytic converters, not factory equipment. But if I can avoid having to pay several hundred to get something cut out that was there from the factory, it seems worth a shot.

@Astrorami He failed me for having 4 catalytic converters which he considered an aftermarket "tampering". Yes, I'm going to get it retested. I wanted to go back to the same inspector today and demand a retest, but it seems they were closed (or at least not answering their phones). I actually scheduled an appointment for tomorrow morning with a "BAR Referee" who is going to look over the smog check results and my car and (hopefully) make a ruling that I pass. He can give me a smog certification right there without having to deal with the first smog inspector.

@Slartibartfast Thanks for the great information! I'm going to call the smog inspector today and explain to him that he got the diagnosis incorrect. I'll bring the information you shared to prove that he was mistaken and demand that he recheck my car and (likely) pass it.

Hi everyone, I hope someone can help me. I just got my 03 Nissan Pathfinder LE from a friend and found out I need to get it smog checked to finish registering the it in my name (I live in California). So, I went to a smog check station and was told that my Pathfinder failed due to a visual inspection. The inspector said I have 4 catalytic converters and should only have 2. The inspector said the two in the engine compartment were stock and the two under the passenger compartment were aftermarket. Not knowing anything at all about the Pathfinder or what my friend had done to it, I just accepted this as a fact. I assumed my friend had at some point installed 2 after market catalytic converters and didn't have the original catalytic converters removed. Now after reading a comment on this forum, I found that the Pathfinder has 4 catalytic converters (although the 2 under the passenger compartment can be called "resonators"?). Can you help me out here? 1. Can you confirm that the 03 Nissan Pathfinder has 4 catalytic converters? Or if it has 2 catalytic converters and 2 resonators? 2. How can I prove this to the inspector so that he will pass my Pathfinder for the smog check? I looked in the Nissan Pathfinder repair manual but it doesn't seem to mention catalytic converters. If there's some documentation somewhere about what these 4 devices are in my Pathfinder, please point me to it so I can print it out and show it to him. Many thanks in advance!