Trying to figure out what’s wrong

[Yoshi]

I just bought a 2019 Kia stinger GT got a steel because it was a rebuilt title with only 38,000 miles.
It has a JB4 tune on it. I don’t know anything about them really trying to figure it out, anyways had an issue where the turbo would spool up and then I would lose power and the check engine light would come on, I shut the car off waited 30 seconds restarted and it was perfectly fine, it did it one more time on my 4 Hour drive home, It did it first and comfort mode then Eco mode didn’t really drive it in sport mode. Around 2000 rpm going about 50-60mph then accelerating is when it happened. Any help would be appreciated.

 

[NS_Stinger]

Sounds like limp mode. What fuel are you putting in it? Do you have any idea what map the JB4 is set to?

 

[Yoshi]

Sounds like limp mode. What fuel are you putting in it? Do you have any idea what map the JB4 is set to?

I’ve only filled up once I put 91 octane in. I do not know what map it’s in. I don’t have the previous owners account information so I can’t get into it. I’m trying to get it unlocked thru the app I had to submit an application it says wait 24 hours

 

[Ohiocruiser]

Remove jb4 and check if it’s doing the same.

 

[Yoshi]

Remove jb4 and check if it’s doing the same.

What process do I have to do to remove it and if I put it in map zero will it turn it off?

 

[NS_Stinger]

Yeah I'd just remove it or easy on the throttle until you can unlock it. The prior owner might have had no idea wyat he was doing and put it on a higher map than he should. If it was me I'd take it off until you can sort out what map it's on.

 

[Yoshi]

Yeah I'd just remove it or easy on the throttle until you can unlock it. The prior owner might have had no idea wyat he was doing and put it on a higher map than he should. If it was me I'd take it off until you can sort out what map it's on.

OK, I’d like to remove it, but I don’t know what I need to do or what I need it all unplug, I don’t wanna start pulling stuff off and mess something up

 

[Yoshi]

Yeah I'd just remove it or easy on the throttle until you can unlock it. The prior owner might have had no idea wyat he was doing and put it on a higher map than he should. If it was me I'd take it off until you can sort out what map it's on.

So I got in and it was on map three which I believe is 93 octane I filled up with 91 octane. I put it in map 0 which says JB4 off i’m gonna take it out for a spin tomorrow and see if I can get it to go into limp mode again or if that fixes the problem

 

[Thomby]

OK, I’d like to remove it, but I don’t know what I need to do or what I need it all unplug, I don’t wanna start pulling stuff off and mess something up

Just trace the harnesses coming from the JB4 box. It intercepts signals between the car's ECU and sensors, so those cables will lead you to the sensors and original stock plugs. You should find:
- MAP & TMAP connectors at a minimum, one on the big intake pipe at the front passenger side of the engine, and one almost straight behind it at the top rear of the engine (JB4's install guide will show you what they look like)
- Possibly "fuel wires" going to the O2 sensors on each side (lower rear of engine). These may have a mini harness between the stock connectors and sensors you can remove, or they may be tapped directly into the stock wires and you can just remove them.
- Least common will be EWG connectors, on each side but at the front, at the turbo wastegate actuators. Same deal here, they'll be short harnesses between stock connectors and the actuators.

So I got in and it was on map three which I believe is 93 octane I filled up with 91 octane. I put it in map 0 which says JB4 off i’m gonna take it out for a spin tomorrow and see if I can get it to go into limp mode again or if that fixes the problem

The general recommendation is Map 1 for 91, Map 2 for 93, Map 3/4 for E30 (5-6 gallons of E85 per tank of premium). But I believe there were fewer maps back then and they were reorganized at some point, so depending on the age/firmware, that may not be true.

I would recommend going into the app settings to check your firmware, and in the meantime, bump it down to Map 0 (stock), do a full throttle run to see if it behaves and check the log, then work your way up through Maps 1 & 2. We can help you check the logs here or you can go on the jb4tech forums.

 

[Yoshi]

Just trace the harnesses coming from the JB4 box. It intercepts signals between the car's ECU and sensors, so those cables will lead you to the sensors and original stock plugs. You should find:
- MAP & TMAP connectors at a minimum, one on the big intake pipe at the front passenger side of the engine, and one almost straight behind it at the top rear of the engine (JB4's install guide will show you what they look like)
- Possibly "fuel wires" going to the O2 sensors on each side (lower rear of engine). These may have a mini harness between the stock connectors and sensors you can remove, or they may be tapped directly into the stock wires and you can just remove them.
- Least common will be EWG connectors, on each side but at the front, at the turbo wastegate actuators. Same deal here, they'll be short harnesses between stock connectors and the actuators.


The general recommendation is Map 1 for 91, Map 2 for 93, Map 3/4 for E30 (5-6 gallons of E85 per tank of premium). But I believe there were fewer maps back then and they were reorganized at some point, so depending on the age/firmware, that may not be true.

I would recommend going into the app settings to check your firmware, and in the meantime, bump it down to Map 0 (stock), do a full throttle run to see if it behaves and check the log, then work your way up through Maps 1 & 2. We can help you check the logs here or you can go on the jb4tech forums.

Ok, what mode should the car be in

 

[Thomby]

Ok, what mode should the car be in

Doesn't really matter, Comfort or Sport will give you more aggressive throttle response than Eco so when you first hammer it you might get onto boost a hair faster, but WOT is WOT in any mode and your logs should confirm that (for Eco you'd need higher Pedal values for a given Throttle position, but once you floor it both will be at 99 or 100).

And just use the auto-logging...there's a setting page where you can adjust where it kicks in, but the default setting of 80% or whatever should be fine. If you use manual logging you'll just fill a spreadsheet with a thousand rows of low/no throttle cruising, when what we need to see is an uninterrupted WOT rip through a couple gears (say 20-25mph up to 70-80 or whatever's reasonable).

 

[NS_Stinger]

If you are running 91 octane I'd keep it at map1, if it runs well and you dont get thrown into limp mode you can try map2. Some guys can only get 91 in their area but have been okay running map2 but it totally depends on the quality of the gas in your area as not all 91 octane and 93 octane are created equal.

 

[Yoshi]

Doesn't really matter, Comfort or Sport will give you more aggressive throttle response than Eco so when you first hammer it you might get onto boost a hair faster, but WOT is WOT in any mode and your logs should confirm that (for Eco you'd need higher Pedal values for a given Throttle position, but once you floor it both will be at 99 or 100).

And just use the auto-logging...there's a setting page where you can adjust where it kicks in, but the default setting of 80% or whatever should be fine. If you use manual logging you'll just fill a spreadsheet with a thousand rows of low/no throttle cruising, when what we need to see is an uninterrupted WOT rip through a couple gears (say 20-25mph up to 70-80 or whatever's reasonable).

Ok ill try however when I get on it a little hard it the turbo is loud and kicks some, I don’t really know how to explain it other than that it just jerks the car but if I get on it slow slowly and smoothly it seams fine, also I’m sending a screenshot of my gauge cluster is this normal?

 

[Thomby]

Ok ill try however when I get on it a little hard it the turbo is loud and kicks some, I don’t really know how to explain it other than that it just jerks the car but if I get on it slow slowly and smoothly it seams fine, also I’m sending a screenshot of my gauge cluster is this normal?

Take a video, pull ODB codes, and run a log on Map 0.

The gauges look fine, but they also aren't telling us much besides the fact that you're cruising along at 10 and 40mph. Ign numbers are sky high because it's a modern car and does creative things when off-throttle to maximize mileage...same deal with the high AFR. We need to see how it behaves under load.