High Flow Cat Question - CELs
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High Flow Cat Question - CELs
Had the newest iteration of the Soul HFCs installed on Friday. Got a CEL about 10 miles after picking up the car but needed to be somewhere so I couldn’t go back. Will follow up with the shop on Monday. Codes are P0420 and P0430. Like I said, codes didn’t pop up right away but I know the Z06 can be sensitive when it comes to emissions readings.
I’ve tried to clear the CEL but am I correct in assuming that the codes won’t clear if there is some type of issue?
I’ve always had Soul HTCs on every high end car I’ve owned and never had issues so I felt comfortable with the choice. Hoping it’s a simple install issue but we’ll see.
I’ve tried to clear the CEL but am I correct in assuming that the codes won’t clear if there is some type of issue?
I’ve always had Soul HTCs on every high end car I’ve owned and never had issues so I felt comfortable with the choice. Hoping it’s a simple install issue but we’ll see.
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Curious why the CEL wouldn’t show up immediately? The emissions systems are so sensitive and pass/fail that I would have thought a CEL would be triggered immediately if an issue was there versus after some driving.
But should I be able to clear the codes and then eventually see them again? I can read the codes but can’t get them to clear.
Last edited by blraider97; Apr 26, 2025 at 05:24 PM.
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You could be right. I’ve reached out to Soul to see what they recommend and go from there. The shop that did the install mentioned that it’s been extremely hit or miss with the HFCs and CELs on the Z06. They recommended adding the “mini cats” as insurance.
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To OP, I hope this doesn't keep popping up. I've had the worlds worst experience with Soul. This CEL keeps popping up on my 24' Z06 and it came back today actually. Car currently has 2500 miles and I've only put on 1k miles on the HFC's. Today is the 5th CEL I think. I'll clear it, it will be fine for a little then it comes back. The O2 spacers are in. Sam from Soul is looking for a fix but I'm half ready to ditch them. I love the sound but dealing with the CEL constantly is annoying.....
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To OP, I hope this doesn't keep popping up. I've had the worlds worst experience with Soul. This CEL keeps popping up on my 24' Z06 and it came back today actually. Car currently has 2500 miles and I've only put on 1k miles on the HFC's. Today is the 5th CEL I think. I'll clear it, it will be fine for a little then it comes back. The O2 spacers are in. Sam from Soul is looking for a fix but I'm half ready to ditch them. I love the sound but dealing with the CEL constantly is annoying.....
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I'll definitely look into that celsync module...
Last edited by Cliff1620; May 3, 2025 at 02:07 PM.
Burning Brakes
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Haven’t had any issues with the plugs. I did tell the shop to use loctite to ensure they were tight because I heard of them being loose. I have a HTC so hard to see and they are still there!
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Each time mine came out there was a very notiicible sputter coming from the engine. Plus the CEL i was gettingg said both banks lean. Once the steel cans and the high temp loctite came in, that code went away and i thought i was in the clear. Then the p0420 started popping up. Soul said I should hear from them this week with an answer
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Please keep us posted. Jerry from Recoil Racing said that he didn’t believe that I would not get a CEL. Sure enough I did. They have 2 C8Zs and constantly they get a CEL and have to reset it every time. PITA
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Burning Brakes
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Yea I have one more year before I have to do an emissions test to register my car again inTX. Hopefully by then there will be a solution or I find a “guy” to pass.
Burning Brakes
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Had the newest iteration of the Soul HFCs installed on Friday. Got a CEL about 10 miles after picking up the car but needed to be somewhere so I couldn’t go back. Will follow up with the shop on Monday. Codes are P0420 and P0430. Like I said, codes didn’t pop up right away but I know the Z06 can be sensitive when it comes to emissions readings.
I’ve tried to clear the CEL but am I correct in assuming that the codes won’t clear if there is some type of issue?
I’ve always had Soul HTCs on every high end car I’ve owned and never had issues so I felt comfortable with the choice. Hoping it’s a simple install issue but we’ll see.
I’ve tried to clear the CEL but am I correct in assuming that the codes won’t clear if there is some type of issue?
I’ve always had Soul HTCs on every high end car I’ve owned and never had issues so I felt comfortable with the choice. Hoping it’s a simple install issue but we’ll see.