P0420 Catalyst System Efficiency Below Threshold (Bank 1) code
#1
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CEL lit up last night on my way home, looks like I'm throwing a P0420 code. I'm going to crawl under and check the 02 sensor voltage. Hoping it's the sensors themselves, but of course am concerned that I'm looking at replacing the CATs.
I have stock turbos and ECU, and I was thinking I would upgrade turbos, ECU and CATs at some point down the road with a tuned package, but I was hoping to put that off a bit. Would it be a bad idea to do 100 cell CATs now and hold off on the ECU and turbo upgrades until later?
Again, hopefully it's just the sensors. But I wanted to get my ducks in a rown in case I need to place an order with Kevin.
I have stock turbos and ECU, and I was thinking I would upgrade turbos, ECU and CATs at some point down the road with a tuned package, but I was hoping to put that off a bit. Would it be a bad idea to do 100 cell CATs now and hold off on the ECU and turbo upgrades until later?
Again, hopefully it's just the sensors. But I wanted to get my ducks in a rown in case I need to place an order with Kevin.
#2
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It should not be a problem to get the 100 cell race cats now, and add the rest later. May I suggest that you talk to kevin about this... he has the large diameter race cats... they are NOT all the same. He can then later sell you the ECU and the matching turbos when you are ready.
How many miles on your car?
How many miles on your car?
#3
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Hi Steve,
That's what I was hoping to hear. The car has only 32k on the clock.
I'm going to do some test rides with the car chip and see what voltages the sensors are logging. Does anyone know what the voltage rages for the 2 sets of sensors are by any chance?
That's what I was hoping to hear. The car has only 32k on the clock.
I'm going to do some test rides with the car chip and see what voltages the sensors are logging. Does anyone know what the voltage rages for the 2 sets of sensors are by any chance?
#4
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32k is way too little to have plugged-up cats... me thinks. Sorry, but I'd bet its the O2 sensors. Too bad you can't start rationalizing the upgrades. Or can you anyway?
#5
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I need to post a few failed/plugged cats.. Miles on the car doesn't factor in when one has lost a turbocharger.. The oil packs the cells with carbon.. However, if you haven't replaced your O2 sensors now would definitely be a good time..
#6
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Thanks guys.
The voltage spikes between bank 1 and 2 on the pre cat sensors seems to be a little off, with bank 1's response a little less crisp than bank 2, so it's possible that b1s1 is a little gummed up. I haven't measured the post-cat sensors, but I think I'll just bite the bullet and replace them all.
Hopefully that should do it for me, but if not.... Kevin, what cats would you recommend if I'm planning on a turbo and ECU upgrade from you, like your stage 1 kit? I probably won't do anything on that front for the next year, but if I'm heading in that direction I figure I might as well plan for it. The car currently has Fabspeed muffler bypasses on it if that makes any difference.
The voltage spikes between bank 1 and 2 on the pre cat sensors seems to be a little off, with bank 1's response a little less crisp than bank 2, so it's possible that b1s1 is a little gummed up. I haven't measured the post-cat sensors, but I think I'll just bite the bullet and replace them all.
Hopefully that should do it for me, but if not.... Kevin, what cats would you recommend if I'm planning on a turbo and ECU upgrade from you, like your stage 1 kit? I probably won't do anything on that front for the next year, but if I'm heading in that direction I figure I might as well plan for it. The car currently has Fabspeed muffler bypasses on it if that makes any difference.