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P0420 and Startified tune

TUX15ST

Active member
Messages
546
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86
Location
SOUTH BOUND BROOK
#21
Yeah thats pretty scary if they really are leaning it out, i doubt its anything crazy but certainly rich is better than lean lol
 


OP
C
Messages
281
Likes
55
Location
Morton Grove
Thread Starter #22
I shouldn't have any leaks because the car is brand new. Maybe it fouled a sensor. I ran the cobb stage 1 almost from new without any issues then I added the Stratified unexpected and it screwed up. I take full responsibility for this because they do say crackle pop is at your own risk. Let's see what happens.
 


Messages
367
Likes
46
Location
Huntington Beach
#23
Well I was running this tune on stock DP/MBRP exhaust, I think I'm gonna take the cracks off for now. Few questions;

According to Strat this is supposed to be Cat safe, is this true?

Whats so bad about getting the cracks from it being lean? TBH when I first got the tune I thought I smelled some burnt cats, but that was only when I was on it and I figured that at least some of the cracks had to come from it running rich.
 


grnmachine02

Active member
Messages
514
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108
Location
Fredericksburg
#24
There's nothing wrong with lean off throttle. Lean a/f and lots of load is where there's a problem. Lean with no load isn't a big deal really. On the stock tune I was seeing decel A/F readings of 42:1.


Sent from my iPhone using Tapatalk
 


me32

1000 Post Club
Messages
1,829
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264
Location
fairfield
#25
This type of feature is also used in the Mustang world for what is called the loppy idle. They do not recommend running cats because there is a possibility of the cats getting damaged. Not saying strat tune will ruin the cat but there is that possibility.
 


Messages
367
Likes
46
Location
Huntington Beach
#26
There's nothing wrong with lean off throttle. Lean a/f and lots of load is where there's a problem. Lean with no load isn't a big deal really. On the stock tune I was seeing decel A/F readings of 42:1.


Sent from my iPhone using Tapatalk
Hmm, I think I'm gonna have to beat the inner child in me down and leave my tune with no cracks on for most of the time. I don't really feel like putting any excess stress on mah car. Gonna miss my pops though :(
 


gabe

Member
Messages
273
Likes
17
Location
Philadelphia
#27
You should be able to clear the code with your accessport. Run it with 1 of the other tunes to see if it comes back. If it doesn't then obviously all is well. However I agree stratified should take a look @ a few logs to see where the issue is coming from.
 


Messages
315
Likes
87
Location
Weymouth
#28
There's nothing wrong with lean off throttle. Lean a/f and lots of load is where there's a problem. Lean with no load isn't a big deal really. On the stock tune I was seeing decel A/F readings of 42:1.


Sent from my iPhone using Tapatalk
Exactly, also running lean actually creates more power. The problem is keeping cyl temps happy and this is why you run a richer mixture under load for safety.
 


OP
C
Messages
281
Likes
55
Location
Morton Grove
Thread Starter #30
Nothing yet because stratified is at Sema. I hope they get back to me ASAP when they get back. I already ordered both O2 sensors in case I have to get a new downpipe.
 


OP
C
Messages
281
Likes
55
Location
Morton Grove
Thread Starter #32
Will do. I've tried every tune including the 0 map from Cobb and I get the CEL. I still find that the car performs the same, though.
 


Messages
387
Likes
59
Location
Fort Carson
#33
Have you looked at the downstream O2 sensor? In a different vehicle, I had hit something on the road and it broke the wire for the downstream sensor. Could be something as simple as that maybe?
 


Messages
387
Likes
59
Location
Fort Carson
#35
Most likely isn't, especially considering the tune, but worth a look for sure. Hopefully you get it resolved either way.
 


OP
C
Messages
281
Likes
55
Location
Morton Grove
Thread Starter #36
Here's what Stratified had to say...
"Hi Carlos,



This is a little odd ? it is the first time we have seen this. How many miles are on the car overall? The code won?t put the car in limp mode or have any running effect, but it will prevent the car from passing emissions. There are a few options:



1. We can turn off the code but it will not be able to pass emissions with the code turned off if emissions testing is required in your area.
2. You can uninstall the AP completely, put some miles on the car, and see if the code is thrown again on the completely OEM tune with the AP uninstalled. If it is you can take it in to your dealer to have this looked at and potentially the downpipe or secondary O2 replaced. We run these on cars with OEM catalytic converters and haven?t seen any issues so it is quite possible it is unrelated to the tune. There is no additional fuel being injected to cause the popping effect.
3. You install a J defouler on the secondary O2 sensors and we do not remove the code. If the code does not pop and readiness monitors set you will be able to pass emissions.


Let us know if you have any further questions.



Thank you,

Alex"

Do you guys know if can access the lower o2 from below without disassembling a bunch of stuff?
 


Messages
387
Likes
59
Location
Fort Carson
#37
You should be able to access the O2 with the car on ramps or jack stands easy enough, without disassembling anything. I haven't been under the car yet, but have never seen a car where you had to remove anything more than maybe an under tray to get to the rear O2
 


OP
C
Messages
281
Likes
55
Location
Morton Grove
Thread Starter #38
I was under the car today to see where everything is at, and yeah, 92FOX, you are right. I guess I can start by replacing the lower o2, and then if that doesn't do it just get a depo racing catted downpipe. The worst case scenario in this whole thing actually is the path to a more efficient FiST.
 




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