Stinger throttle cuts under acceleration

[WSTINGER]

Hi



I am new to the forum and am hoping I could hear from anyone else that's had this issue in Australia. I have Googled and have seen posts of the same issue in the US.

I have a 2022 GT Stinger, with K&N filter kit and GFB blow off valves fitted. I have pretty much had this issue since I bought the car last December, when accelerating from stop the car will rev and usually between 2000-3000rpm the throttle will drop for about 2 seconds and then the throttle comes back. It also happens around 5000rpm occasionally. I reported the issue to Kia dealership prior to the 3000km service and they couldn't identify the issue and on the day I was unable to replicate it.


I have since taken it for the 10000km service and the same thing happened again, unable to replicate. I managed to video the issue and sent to the Kia dealership and took my car to them last weke and they replaced the fuel pump and said it was fixed... I picked the car up and it was still doing the same thing, I took the car straight back. They had one of their technicians come for a drive and he managed to record it. They have now had the car for nearly a week and I have been asked today to remove the air filter kit and BOV.

Has anyone had or heard of this issue? I am not convinced these minor mods are the issue, especially as this is my 2nd Stinger and the previous one had the same minor mods with no issues.

Any advice or info would be appreciated.

 

[Snicklefritz]

Starting with the '22 refresh, the valved exhaust gets over boost sometimes. Your mods can make it happen more often. Kia is within their bailiwick telling you to take those mods off before proceeding. This is not an Aussie thing.

 

[rtv900]

what does "the valved exhaust gets over boost" mean?

 

[bfglitch]

In the US, the 22+ have valved/bi-modal exhaust and during the winter when the temps are cool, they have a tendency to overboost, especially with intake mods. The odd thing is the Australian stingers had valved/bi-modal exhausts for years, even prior to the US 2022+ facelift.

 

[Snicklefritz]

In the US, the 22+ have valved/bi-modal exhaust and during the winter when the temps are cool, they have a tendency to overboost, especially with intake mods. The odd thing is the Australian stingers had valved/bi-modal exhausts for years, even prior to the US 2022+ facelift.

That's true, I had forgotten that detail. So, @WSTINGER will likely point that out, and his point still stands, his earlier Stinger, also with valved exhaust, did not do this. And regardless, my point still stands, Kia can tell him to remove his mods, or there's the door bucko.

 

[WSTINGER]

Ok so of this is the issue then what are my options?
a) remove and go back to standard.
b) leave them in and live with it.
c)???

Oh just on the cold point, the car has been doing this in cold weather and hot weather.
And I've also read about Stingers doing this without mods..

 

[rtv900]

In the US, the 22+ have valved/bi-modal exhaust and during the winter when the temps are cool, they have a tendency to overboost, especially with intake mods. The odd thing is the Australian stingers had valved/bi-modal exhausts for years, even prior to the US 2022+ facelift.

but what does a valve in the muffler have to do with overboosting?
cold or not

 

[bfglitch]

but what does a valve in the muffler have to do with overboosting?
cold or not

That's the thing, I don't think it does. I think there's something else on the 22+ that is causing the issue. It doesn't matter what mode I'm in and whether the valves are open or not. It seems to mainly happen while deep in the throttle going 2nd to 3rd. During the shift the boost spikes and causes an overboost. I was having this issue bone stock in both sport (valves open) and comfort (valves closed). The issue got worse when I added the AFE intakes which makes sense as they're technically a bit less restrictive than the stock air boxes.

Also technically the exhaust is tied to boost. Exhaust is used to drive the turbine.

As for cold or not, cold air is more dense = more likely to overboost

Ok so of this is the issue then what are my options?
a) remove and go back to standard.
b) leave them in and live with it.
c)???

Oh just on the cold point, the car has been doing this in cold weather and hot weather.
And I've also read about Stingers doing this without mods..

Sadly I don't really have answers to your questions. Most folks with the 22+ that have had the issue and got annoyed with it have either been living with it since it mainly happens during the cold (air is more dense), got rid of it (not sure how many but I know of a couple), been doing tunes which have resolved the issue for them.

Have you tried going back to stock to see if the issue went away?

I honestly think the issue is either tied to the stock ECU programming on the 22+ (which is just a total guess because I have no clue if Kia made any changes in the ECU programming after the facelift), or something to do with the wastegate, or possibly both, or neither. At this point it's all hypothetical.

The only way it has a chance to get resolved is if Kia can replicate the issue consistently, but to do that they'll need to go WOT which (I'm not sure about in Australia) but I've heard Kia dealerships in the US "aren't allowed" to do.

 

[WSTINGER]

That's the thing, I don't think it does. I think there's something else on the 22+ that is causing the issue. It doesn't matter what mode I'm in and whether the valves are open or not. It seems to mainly happen while deep in the throttle going 2nd to 3rd. During the shift the boost spikes and causes an overboost. I was having this issue bone stock in both sport (valves open) and comfort (valves closed). The issue got worse when I added the AFE intakes which makes sense as they're technically a bit less restrictive than the stock air boxes.

Also technically the exhaust is tied to boost. Exhaust is used to drive the turbine.


Sadly I don't really have answers to your questions. Most folks with the 22+ that have had the issue and got annoyed with it have either been living with it since it mainly happens during the cold (air is more dense), got rid of it (not sure how many but I know of a couple), been doing tunes which have resolved the issue for them.

Have you tried going back to stock to see if the issue went away?

I honestly think the issue is either tied to the stock ECU programming on the 22+ (which is just a total guess because I have no clue if Kia made any changes in the ECU programming after the facelift), or something to do with the wastegate, or possibly both, or neither. At this point it's all hypothetical.

The only way it has a chance to get resolved is if Kia can replicate the issue consistently, but to do that they'll need to go WOT which (I'm not sure about in Australia) but I've heard Kia dealerships in the US "aren't allowed" to do.

Thanks for the detailed response mate and sharing your thoughts.

I am 97% certain this issue was happening prior to the mods - memory is a little fuzzy as it was 11 months ago now. I have booked in for Thursday to have the mods removed and restored to factory but I am hoping for another option. I have been googling the initial info shared by @Snicklefritz and also yourself and there is discussions on the WG being part of the issue, not specific to the Stinger though..

I have a JB4 which I need to fit and am wondering if I should get the JB4 EWG Add On Connectors to see if this will better control the WG.

I also have the Xforce Varex Valved Cat Back Exhaust System ready to fit, but am now hesitant to do so at this point, but possibly if it is to do with the valved exhaust could this potentially minimise the occurrence of over boost?

Thanks

 

[bfglitch]

For the JB4, I believe the EWG wires can possibly help, but there has been some chatter about using them and causing other issues if you want to eventually get an ECU tune. You could always email Terry at BMS to get some input from him.

As for the exhaust, I really don't think it'll make that much of a difference but once again, I really don't know. Only mods I've done to my '22 have been the intakes, sway bars, and wheels.

Although then again, re-reading your initial post, you may be experiencing a completely different issue. The overboost issue I'm talking about, when it happens all boost is cut off after it occurs and you lose all power/acceleration until you restart the car. If you hook up a code reader to the car you'll have a pending code P0234. If it happens 2-3 times in a row it'll finally trip a CEL. After that it leaves boost completely disabled.

Either way I'm not surprised they want you to return the car to stock. They probably want to rule out the aftermarket parts being the cause. Many of the dealerships here in the states would have just immediately blamed the aftermarket parts and would say they won't even look at it.

 

[WSTINGER]

For the JB4, I believe the EWG wires can possibly help, but there has been some chatter about using them and causing other issues if you want to eventually get an ECU tune. You could always email Terry at BMS to get some input from him.

As for the exhaust, I really don't think it'll make that much of a difference but once again, I really don't know. Only mods I've done to my '22 have been the intakes, sway bars, and wheels.

Although then again, re-reading your initial post, you may be experiencing a completely different issue. The overboost issue I'm talking about, when it happens all boost is cut off after it occurs and you lose all power/acceleration until you restart the car. If you hook up a code reader to the car you'll have a pending code P0234. If it happens 2-3 times in a row it'll finally trip a CEL. After that it leaves boost completely disabled.

Either way I'm not surprised they want you to return the car to stock. They probably want to rule out the aftermarket parts being the cause. Many of the dealerships here in the states would have just immediately blamed the aftermarket parts and would say they won't even look at it.

Thanks again mate.

Yeah the throttle only drops for 1-2 seconds and then its back, I have videos of this, but cant share videos on the post..
Unfortunately its not consistent and I haven't yet identified a way to replicate it consistently.. But saying that if it did it consistently Id have lost my mind haha

 

[rtv900]

right exhaust drives the turbos, but those valves are a mile away from that. If OP modded his wastegates I'd say for sure that's the issue.
The BOV maybe, but that just dumps the boost if you slam the throttle shut so if he's dumping to atmosphere instead of recirculating like modern cars do then he'd get a rich situation for a tiny period of time since that was metered air. But still, rich isn't that big of a deal for a second.

OP, so you didn't mod your wastegates in any way correct?
Also, I have a 22 also, and my boost peak when steady seems to be right around 10psi, maybe 11.
What are you seeing?

 

[WSTINGER]

right exhaust drives the turbos, but those valves are a mile away from that. If OP modded his wastegates I'd say for sure that's the issue.
The BOV maybe, but that just dumps the boost if you slam the throttle shut so if he's dumping to atmosphere instead of recirculating like modern cars do then he'd get a rich situation for a tiny period of time since that was metered air. But still, rich isn't that big of a deal for a second.

OP, so you didn't mod your wastegates in any way correct?
Also, I have a 22 also, and my boost peak when steady seems to be right around 10psi, maybe 11.
What are you seeing?

Hi mate, no nothing modded on the wastegates. I'll have to get back to you on the psi this afternoon after work.
Cheers

 

[D.J.]

I managed to video the issue and sent to the Kia dealership and took my car to them last weke

Where is the video?

 

[WSTINGER]

Where is the video?

unfortunately I can't post here, seems images only are allowed.. Ill try to convert to a gif

 

[WSTINGER]

unfortunately I can't post here, seems images only are allowed.. Ill try to convert to a gif

No good, the gif makes it jumpier than the original when my girl was hanging on for her life - her words haha
Ill try get another and post later this arvo.

 

[D.J.]

unfortunately I can't post here, seems images only are allowed.. Ill try to convert to a gif

Host on another platform

YouTube
Imgur
Streamable

 

[WSTINGER]

Host on another platform

YouTube
Imgur
Streamable

here you go - ht tps :// streamable .com/ ul10gp
remove the spaces as the forum didnt let me share a URL

just before 5000rpm you'll see it drop off
As I mentioned bit jolty as the girl was hanging on for her life. I will try and get another though.

 

[D.J.]

here you go - ht tps :// streamable .com/ ul10gp
remove the spaces as the forum didnt let me share a URL

just before 5000rpm you'll see it drop off
As I mentioned bit jolty as the girl was hanging on for her life. I will try and get another though.

And this video is wide open throttle?

Sounds like the throttle slams closed twice during that pull

Odd

 

[WSTINGER]

And this video is wide open throttle?

Sounds like the throttle slams closed twice during that pull

Odd

yeah man that was flooring it. I did notice a couple of times over the last 2 days and will try again this arvo when I go out.. if I dont floor it and but still giving it a reasonable amount of gas, it seems to do it.
it so fkn inconsistent..