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The purge valve had failed in some cases after 20k miles or less. I have a 2018 with 19k miles, I'm having the issues once in a while. So, I should be ordering one soon. The symposer is attached to the manifold, if it has a code, it has a malfunction. Do the delete and the purge to start. It has to be done anyway. You can go from there if it doesn't fix your problem.
 

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Discussion Starter · #22 ·
The purge valve had failed in some cases after 20k miles or less. I have a 2018 with 19k miles, I'm having the issues once in a while. So, I should be ordering one soon. The symposer is attached to the manifold, if it has a code, it has a malfunction. Do the delete and the purge to start. It has to be done anyway. You can go from there if it doesn't fix your problem.
Compression tested today, came back:

150
150
150
130

I don't take that as reason to be alarmed, it was the last one we took as well for cylinder 4. As far as fueling goes, I logged the injector flow on a pull where I ramped into the throttle a lot more compared to flooring it before. This is what I meant before, where if I am not flooring it it's drivable, even this is more than I normally do for this reason. Below is the log with the fuel mass injector numbers.

Datalog with Fuel Mass Injector Reading

As far as the AFR goes, I was under the impression that being a number lower than 14.70 was on the richer side, seeing that when I am off the gas and coasting the Cobb AP reads numbers in the 40s. Unless the issue is that it is not adding enough additional fuel, I am not understanding there. Nonetheless, I have appreciated the help so far and appreciate any thoughts on this moving forward.
 

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I’m no tuner but that looks way to lean. You have a long stretch of 60-80 percent throttle and your afr stayed up above 14:1

also cylinder 4 is quite a bit lower, I can’t do math but I think that’s 13 percent lower which could be worth more investigation. I’m in the same boat as you but after time has passed and still haven’t figured this out it’s got worse and does this at any throttle position around 5k rpm’s every time. I also have lower compression in one cylinder and will be doing a leak down test next. Will be following this thread and hope we can get this sorted out asap!
 

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Sorry, I could not find you thread. Check for boost leak. If you can access the turbo from the passenger side or underneath, try to move the wastegate to see if it has some play, the bushing wears out and it can't seat properly. Take off the BPV, if it is the original, it could be leaking by now.
 

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Discussion Starter · #25 ·
I’m no tuner but that looks way to lean. You have a long stretch of 60-80 percent throttle and your afr stayed up above 14:1

also cylinder 4 is quite a bit lower, I can’t do math but I think that’s 13 percent lower which could be worth more investigation. I’m in the same boat as you but after time has passed and still haven’t figured this out it’s got worse and does this at any throttle position around 5k rpm’s every time. I also have lower compression in one cylinder and will be doing a leak down test next. Will be following this thread and hope we can get this sorted out asap!
Sorry, I could not find you thread. Check for boost leak. If you can access the turbo from the passenger side or underneath, try to move the wastegate to see if it has some play, the bushing wears out and it can't seat properly. Take off the BPV, if it is the original, it could be leaking by now.
Figured I’d update. Now confirmed that it’s spitting white smoke when it misfires, had someone following me pay attention to it. Going to Panda Motorworks next week to see what they can find, at this point it’s more guess work on my end anyways with no clear way to go.
 

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Discussion Starter · #27 ·
Oil levels and coolant good? Any odd coloration to oil?
All good there, just had the oil changed not long ago and problem started long enough before that. No issues with coolant either, only overheating problem was relative to the fan control module going out, and replacing that fixed it as the radiator fan just wasn’t even firing. No fluids underneath the car ever.
 

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Figured I’d update. Now confirmed that it’s spitting white smoke when it misfires, had someone following me pay attention to it. Going to Panda Motorworks next week to see what they can find, at this point it’s more guess work on my end anyways with no clear way to go.
Good luck at panda hope it works out for you. People have some very mixed feelings about them around here. Let us know what they find and how your experience with them is.
 

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Discussion Starter · #29 ·
Good luck at panda hope it works out for you. People have some very mixed feelings about them around here. Let us know what they find and how your experience with them is.
Appreciate it, I’ll be sure to post what they find. Have a bit of a professional relationship with them because they are a dealer for the company I work for, so I should be good to go hopefully.
 
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