3.3TT P2098 code after Jun BL downpipe.

[drpepperguy]

Hi all,

I had several things done to my 2019 kia stinger gt1 at a performance shop which include bms occ, bms air intakes, velossa tech big mouths, hks spark plugs as well as the jun BL downpipe (in addition to my mbrp catback that I got about a week earlier. About a day after getting the car back my CEL lit up. Went to an auto store and they said it was a code signifying the engine is running lean. I went ahead and made an appointment at my dealer. I have seen things online from bad sensors to exhaust leaks. My question is is my engine 'actually' running lean or are the sensors misinterpreting this because of the exhaust I have added? Anything I can do in the meantime? Of note I believe my car is in so called "limp" mode while the CEL is still on. I do plan to install my JB4 later (after dealer visit). Anything helps, thanks!!

-newbie

 

[SRV]

The first thing I would do is verify the exhaust is installed correctly.

It is no coincidence that the issue cropped-up immediately after getting the car back after an exhaust install.

 

[One Bad Ass Car]

Yes! I have a 2018 Stinger GT2 and had my motor done with those sand upgrades got my car back and my car instantly through that same code the same day I got my car back from my tuner after about 20 minutes of driving with also the car seemed to stumble at the beginning of acceleration also seem to give the car a “drag” feel to it when accelerating so I freaked out called my tuner right away and was told that it was common for this code to pop up after the upgrade that the car is like “figuring out” the new upgrade and to just clear the code through the JB4 and since I did the code hasn't came back on so hope it will ll be ok. Should I have to worry?????????

 

[Flynfishmedic]

You may have to get EWG wires if you do not already! Anytime you make modifications to the exhaust that impact the "back pressure" required by the turbos you have to tune for them. Clearing the code will most likely not correct the issue and the car is not figuring out the new additions!

 

[StingerMG]

You can try resetting the fuel tables for the car. To do so just disconnect the negative battery connector for 30 mins plus. When you start the car back up, your ECU's adaptive fuel tables should be reset (just drives around to rebuild). I have the Jun.BL secondary downpipes, while I never got a CEL after the install, resetting the adaptive fuel tables became my standard process after adding a bolt on mod.

Also it's very easy to overboost the Stinger GT with intakes and exhaust mods. A piggyback tune or ECU tune will keep it from overboosting. A JB4 with the EWG wires will help if you continue to have issues but I've only seen the EWG wires to be 100% necessary if you change the primary downpipes.

3.3TT - Bolt on overboost (no tune)

So I decided to test how easily one could overboost the Stinger GT with bolt ons. I have ram air ducts, intakes, charge pipes, an intercooler, secondary downpipes, and a catback exhaust. It was 29F outside and I disable my Racechip GTS before starting the engine. Once my engine oil got up to...

stingerforum.org

 

[JHolding]

impact the "back pressure" required by the turbos you have to tune for them.

I always cringe at statements about the necessity of back pressure. In a perfect world, 0 back pressure is the required amount.

People often spoke of the requirement of back pressure from the olden days of carburetors, as they would put free flowing exhaust on their cars without re-jetting the carbs and end up burning holes in pistons. Their only diagnosis for what happened is that the engine must require back pressure. Unfortunately, that has stuck in everyone's minds as it was passed down from generation to generation that engines NEED back pressure to survive.

For street driven machines that require exhaust systems to be legally driven on the roads, we need to strike a balance between back pressure and exhaust velocity/scavenging. Which is why you normally have maximum exhaust size recommendations. Too large of a diameter exhaust, you get turbulence between the exhaust pulses that can cause backpressure, too small of an exhaust, intant back pressure...


This is a good read:
Is Back Pressure Good For Turbo? | Car Performance Boss

TLDR quote from the above link:

"If you are too lazy to read – Back pressure is not good for turbo (or for anything else). With back pressure, exhaust gases cannot easily flow in the exhaust system. Which means they will spool the turbo with reduced force – resulting in power loss and more turbo lag. "

 

[Flynfishmedic]

This is why I put it in quotation marks. As it is not truly back pressure but easier explained as such.

 

[JHolding]

This is why I put it in quotation marks. As it is not truly back pressure but easier explained as such.

Got it! I wondered why you put quotes there.