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Discussion Starter #1
well, driving to work today and the SES popped on.. great.. didn't feel anything different.. after work i went to auto zone and code reader showed p0420.. not surprised as I had to replace the other side cat & 02 about a year ago, only matter of time before the other one goes right?

anyways.. that i can deal with i know what the issue is and how to fix it. weird thing is on the way home i also noticed the oil pressure gauge pegged to high. based on research( mostly this site thanks THENEWX!!) that should just indicate that the sensor is bad and needs to be replaced., fine i can handle that.

thing that is bugging me is.. why both about approx the same time.. i don't see any way they are related expect bot are sensor related.. could it be some electical issue? I have read on here about the IPDM issues.. could that be involved?? pure coincidence?

first thing ill do is change the oil sensor, I did just do an oil change with the regular castrol gtx HM 5w30 and a blue puraltor filter.. never had issues with those.

can I put the actual gauge in there or just the dummy version which is what it has from factory?

Im going to do this cat replacement, i had the dealer do it last time but i cant afford that again... though this time i think ill change the 02 sensor first and see if that is the issue instead of the actual cat itself.

any other thoughts?

I have also been thinking about replacing the X.. I love it but it is becoming a bit high maintainence.... but a really dont want a car pmnt. .. decisions!

and really about the only thing i want to replace it with is a new X p4x...
 

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I feel you on the high maintenance (you liked my last post). Unfortunately I dont have answers for most of your questions, but I can speak to coincidences.

I work in theater with very complex technical systems. One thing that I have learned all to well through my work over many years is that coincidences happen. I had a situation just a few weeks ago where I was troubleshooting a problem. I swapped out a component and still had the problem. So i eliminated that component as the source of the problem and went about troubleshooting (unsuccessfully) the rest of the system. Coming in with a fresh mind the next day I scrutinized every check I made the day before. Turns out that both components I had swapped were bad. Out of a drawer full of these components I had grabbed the only two that were bad. As I was checking them somebody said to me "c'mon they wouldn't both be bad!" Coincidences happen.

My suggestion would be to forge ahead addressing the two as separate problems while still being suspicious that they could be related. Always keep any open mind.
 

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The 2 are not related at all. The O2 sensors are on the PCM/ECM and the oil pressure sensor is direct to the Instrument Cluster.
Just replace the sensor and you good to go with the oil pressure


Sent from my iPhone using Tapatalk
 

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Discussion Starter #4
parts arriving today: new OEM oil pressure sensor, new non oem cat, passenger side primary, and some spare gaskets. Hoping the o2 is still ok and its just the cat.. we shall see.

sprayed the bolts down with some pb blaster last night, they are pretty rusty.. but since ill have new hardware i can cut them off if need be. access doesnt seem to be too bad once iget the fender liner off.

wish me luck!

question: should I drain the oil first? im seeing confilcting reports of how much oil will come out of the pressure sensor hole once its revmoed, I might just paly it safe and drain it first, its pretty new oil so i might save it and pout it back in if i do drain it.. thoughts?
 

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Discussion Starter #5 (Edited)
Well i managed to get the cat and oil pressure sensor replaced today, so far so good. the cat has a 3 yr / 30k mile warranty on it, so as long as I get that out of it ill be happy. I purchased one from amazon for just $120 bucks, had it in less than 48 hrs. fitment was almost perfect. I did have to use 2 gaskets on the rear end to get it flush but that was it. kinda wish i would have tried a non oem oil pressure sensor as I could have saved a good bit. replacing this was very easy and only a small amnt of oil, like 1-200 ml drained out of the oil pressure sensor hole(bung?). i did have the front end jacked up though, so if it were flat maybe more would leak out.

the hardest part by far was removing the old cat. the bolts all came off surprisingly easily, including the 02 sensor. once they were all off i had to use a ratchet strap to pull the exhaust back far enough to allow the cat to drop free. Installation of the new one was a breeze comparatively as it did not have fixed studs, but came with nuts and bolts. upon start up the SES light was off and Oil Pressure guage reads directly in the middle, just like it always has.

Will up date if something changes.

PS:

I was going to buy a walker cat, but after looking at product photos and reviews, I bought this no name one from amazon prime. In the pictures online the welds and just overall product looked so much better than the walker ones. the product i recieved looked very much like the one pictured online. to me it looked like better quality for like half the price. almost seems too go to be true... time will tell.
 

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Discussion Starter #6
Ses came on yesterday. I haven't had a chance to get the code scanned. I think it's about time I get my own obdii scanner! I bet it's going to the the pass upstream o2. Same thing happened after the first cat was replaced. I hope so as that's relatively easy.
 

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Discussion Starter #7
Ok, code is PA200; not what i expected, for several reasons. Bank 1 sensor 1 reading bad. I replaced that cat and sensor within last year or so. i was thinking it would be a Pa203 which it think is the bank 2 sensor 1 as i just replaced that bank 2 cat.

Started doing some research and it looks like this code can be a bit of a mystery until i found this video which helps show and explain that even though the code thrown is for bank 1 sensor 1, the issue is with bank 1 sensor 2, the down stream one!


so what do you guys think?

im tempted to replace the rear one, and then if that doesn't solve it ill try to get them to replace the front one under warranty if its within 1 yr??

would you guys do anything differently?
 

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I had a P2A00 code when I had a leak between the passenger primary and secondary cat. The flange on the primary that bolts to the secondary had rusted and was leaking. So either you have a leak, or the downstream sensor is bad.
Check if you need to tighten up that flange.
 

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Discussion Starter #10
crazy thing is there is a small leak on the passenger side cat exit to exhaust inlet, it seems to seal up once hot as i only notice it on start up.

but i cant feel or hear anything as far as a leak on the drivers side, so im guessing its the rear o2 sensor. new one arrives tomorrow, hopefully before dark lol.
 

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Discussion Starter #11
well i just replaced the driver secondary o2 sensor and it seems to have cleared the P2A00 for now at least.

I checked for exhaust leaks and while the driver side is fine, I noticed that the passengerside exhaust flange that goes from the primary cat into the exhaust exit pipe is cracked.. right at the weld.

so ill be figuring out what to do with that. its a small leak right now but i shouldnt let it go too long like that. It might be time to replace the danm exhaust..
 
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