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Why could my Stage 1+ Unitronic GTI be losing power?

wasbaggedonce

Autocross Champion
Location
PA
Car(s)
2020 GLI Autobahn
Like the title says, Stage 1+ (93 Octane) Unitronic tune. Some background: The car has 36,000 miles and has been running 93 octane for months now even though the tune is new. However, when I'm taking the on ramp to the interstate and I'm WOT in third gear, the engine cuts off around 5500rpm. It's not the clutch slipping. It's just like the engine bogs down and loses power and the RPMs briefly drop. No codes or CELs thrown. Only other "mods" are the intake snow grate removal, K&N oiled filter, and a CTS turbo inlet pipe.
 

maxwell

Drag Racing Champion
Location
Pitt
Car(s)
2018 GSW 6MT 4motion
miles on the plugs? any logs? Has this issue presented itself since tune, or was it fine for a while after being flashed?

doesnt appear to be a turbo or clutch issue but hard to say without more detail.
 

wasbaggedonce

Autocross Champion
Location
PA
Car(s)
2020 GLI Autobahn
miles on the plugs? any logs? Has this issue presented itself since tune, or was it fine for a while after being flashed?

doesnt appear to be a turbo or clutch issue but hard to say without more detail.
I’m guessing 36,000 miles on the plugs. I bought the car CPO at 30,000 miles and there’s nothing saying they changed the plugs.

The issue has been present since the first WOT third gear pull with the tune. Never before, and almost every third gear WOT pull since. No issues with any other gears though. I can run second or fourth up to 7000rpm without issues. I didn’t pull any logs, but I can.
 

maxwell

Drag Racing Champion
Location
Pitt
Car(s)
2018 GSW 6MT 4motion
Yeah you need to address the plugs ASAP, IMO. Cheap insurance. RS7

EDIT: I guess it's odd that it's not 'missing' in other gears. Post logs.
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
If it was the plugs it wouldn't only happen in 3rd gear. Nave you taken 4th gear past 5500 RPM 's?
 

rye0pa

Go Kart Newbie
Location
NJ
I think I would be checking a boost leak of some sort.
 

FlyingNugget

Go Kart Newbie
Location
Toronto, Canada
I’m guessing 36,000 miles on the plugs. I bought the car CPO at 30,000 miles and there’s nothing saying they changed the plugs.

The issue has been present since the first WOT third gear pull with the tune. Never before, and almost every third gear WOT pull since. No issues with any other gears though. I can run second or fourth up to 7000rpm without issues. I didn’t pull any logs, but I can.
Very strange that 2nd and 4th work flawlessly.

Perhaps it's a ECS/XDS/Traction control function -- 2nd happens too fast to notice, and 4th doesn't have enough power to activate the function.

I'd be looking at plugs as an easy quick solution. If not that, will probably need logs to figure it out.
 

Visceral

Go Kart Newbie
Location
Northbrook, IL
I've been running the Uni 1+ tune for a couple years and have put approximately 50k with the tune. Never had "exactly" what you are referring to but have noticed that the engine seems to run out of legs past 6k. I've always short shifted. That said, I understand that the issue I am talking about has more to do with the IC than anything else. That your rpm's drop is what I cannot figure out. Does it feel like the rpm's drop or are seeing the gauge actually register a drop in rpms?
 

wasbaggedonce

Autocross Champion
Location
PA
Car(s)
2020 GLI Autobahn
I've been running the Uni 1+ tune for a couple years and have put approximately 50k with the tune. Never had "exactly" what you are referring to but have noticed that the engine seems to run out of legs past 6k. I've always short shifted. That said, I understand that the issue I am talking about has more to do with the IC than anything else. That your rpm's drop is what I cannot figure out. Does it feel like the rpm's drop or are seeing the gauge actually register a drop in rpms?
It’s nothing like that. It’s the engine completely cutting power at 5500. Yes I see the RPMs briefly drop. Maybe cutting off fuel to the engine. I’m not sure what’s happening.

Haven’t had a chance to pull logs, but I’ll have new plugs in tomorrow or Saturday and report back.
 

Dog Dad Wagon

Autocross Champion
Location
Go Birds
Car(s)
16 Touareg TDI
It’s nothing like that. It’s the engine completely cutting power at 5500. Yes I see the RPMs briefly drop. Maybe cutting off fuel to the engine. I’m not sure what’s happening.

Haven’t had a chance to pull logs, but I’ll have new plugs in tomorrow or Saturday and report back.

it sounds more like fuel cut than timing pull. Fuel trims would be good to see in a datazap
 

OBP

Go Kart Newbie
Location
ChiRaq
Because I like poking a hornets nest.....
Weren’t you considering Uni vs APR??

If you only made one change and only after that change did your issue pop up, then the culprit of that issue is likely that change.

Uninstall and test again for confirmation. If it clears back up with the stock tune, re-install the Uni tune and test again. If the problem comes back, you have your answer.

ps.. is it too soon to say you should have gone COBB/EQT? (I kid, I kid.)
 

Dog Dad Wagon

Autocross Champion
Location
Go Birds
Car(s)
16 Touareg TDI
Because I like poking a hornets nest.....
Weren’t you considering Uni vs APR??

If you only made one change and only after that change did your issue pop up, then the culprit of that issue is likely that change.

Uninstall and test again for confirmation. If it clears back up with the stock tune, re-install the Uni tune and test again. If the problem comes back, you have your answer.

ps.. is it too soon to say you should have gone COBB/EQT? (I kid, I kid.)

well, i get what you’re saying but stock tune is so conservative that it allows for normal operation on aging parts like plugs and fuel pumps. If you’ve got a small fueling issue, it won’t show itself until you’re pushing more air and fuel.
 
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