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Installed intake and got a code. HELP!

maserati

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2 weeks ago I installed a catless downpipe and flashed MHD Stage 2. No issues. Few days ago I installed an MST intake and turbo inlet. Last night I was driving and got a CEL with code 118602 - Mixture control: Mixture gas after catalytic converter too lean. Would this have something to do with the intake? Possible leak somewhere? I’m pretty sure I tightened everything. The only thing I’m thinking is this hose on my turbo inlet. Does this look like it can be the issue?

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itzTang

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make sure no intake leak. looks like that can be pushed more in? reset and see if code returns. maybe o2 sensor harness damaged during cat install? or can just be from going catless.
 
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IMO that should have nothing to do with the intake. Agree that breather looks like it could be pushed in a little better, that thing is a bish to get fitted properly. But as it is I doubt it’s leaking, that’s not pressurized.

Guessing your ECU finally got tired of the catless smell, though I assumed flashing that MHD file would eliminate the standard CEL from catless DP though?

are you sure the intake connection to the turbo inlet is good?
 
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maserati

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Damn that sucks. I have no idea what it can be. I’m gonna take apart the intake and put it back together. I’m pretty positive the downpipe and sensors are good. I installed it 2 weeks ago and didn’t get any cel till just now like 50 miles after installing intake
 

Speed Logic

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Damn that sucks. I have no idea what it can be. I’m gonna take apart the intake and put it back together. I’m pretty positive the downpipe and sensors are good. I installed it 2 weeks ago and didn’t get any cel till just now like 50 miles after installing intake
Usually those codes are related to the Downpipe/O2 Sensors.

With that said for the Intake be sure to snap the connection in all the way as others have mentioned above. It looks like it can go it a bit further. Also there should be a clamp on the silver aluminum fitting where it connects to the Black silicone Inlet which looks to be missing. Try to add a clamp on there and see if any changes once you erase the codes.
 
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maserati

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Usually those codes are related to the Downpipe/O2 Sensors.

With that said for the Intake be sure to snap the connection in all the way as others have mentioned above. It looks like it can go it a bit further. Also there should be a clamp on the silver aluminum fitting where it connects to the Black silicone Inlet which looks to be missing. Try to add a clamp on there and see if any changes once you erase the codes.
Oh damn I didn’t realize that small little clamp goes there! Thank you very much. I’ll try it out
 
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maserati

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So I took it apart and tightened that little port. Put everything back nice and snug and I still have a boost leak somewhere. I can’t figure it out. Is the inlet connection supposed to be able to wiggle around? The metal pipe that attaches with the little spring thing
 

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You’re chasing the wrong thing. The code is for the cat. What are your current fuel trims? Is the cat check turned off in the tune?
 

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So I took it apart and tightened that little port. Put everything back nice and snug and I still have a boost leak somewhere.
Our generation of b58 is does not have a MAF, so a leaky intake or charge pipe will not affect AFR or fuel trims.
 
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maserati

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You’re chasing the wrong thing. The code is for the cat. What are your current fuel trims? Is the cat check turned off in the tune?
How do I check fuel trims. Yes I did aftermarket cat option in the MHD tune
 
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maserati

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would it be lambda 1 AFR? I did a mini log and it says 14.7. And my boost was 9.2 max. Won’t go above that.
 

shaloot

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So I took it apart and tightened that little port. Put everything back nice and snug and I still have a boost leak somewhere. I can’t figure it out. Is the inlet connection supposed to be able to wiggle around? The metal pipe that attaches with the little spring thing
Like others have said I think you are chasing 2 different issues, but that said take a peak at this thread, it seems MST started shipping this metal turbo inlet connector even though their overall design and big silicone piece is really designed to connect directly to the turbo.

https://www.supramkv.com/threads/mst-v3-inlet-intake-install.28726/

edit: also if you did use the metal connector, did you take the orange gasket out of the stock intake and put it into the MST? Again, should be unrelated to your code but still impacts the intake install.
 
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maserati

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Like others have said I think you are chasing 2 different issues, but that said take a peak at this thread, it seems MST started shipping this metal turbo inlet connector even though their overall design and big silicone piece is really designed to connect directly to the turbo.

https://www.supramkv.com/threads/mst-v3-inlet-intake-install.28726/

edit: also if you did use the metal connector, did you take the orange gasket out of the stock intake and put it into the MST? Again, should be unrelated to your code but still impacts the intake install.
Yes I did use that metal coupling and it seems a little loose! I did use the OEM orange gasket too. That person in the thread said he stopped using the metal coupling and instead put the silicone inlet directly on. Do you think I should do that? And just get rid of the metal one?
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