|
|
|
|
Thread Tools | Display Modes |
07-20-2021, 08:04 PM | #1 |
Scooby Newbie
Member#: 525654
Join Date: Jul 2021
Location: Long Island, NY
Vehicle:2019 WRX WRB |
Bone stock 2019 WRX, frustrating power loss driving through the mountains
Hello all! I drive a totally stock 2019 WRX, sitting right at 25,000 miles. In the nearly 3 years I've owned the car, I've taken 5 or 6 trips into the mountains around the Tail of the Dragon on the border of NC and TN. Each time, I experience frustrating power loss mainly on the highways and mountain passes in the area. In some cases, I will be traveling downhill at 3,000 rpm and lose speed, even while hitting 2 or 3 PSI of boost. This is most noticeable in 5th and 6th gear, where even at 70 to 80 mph, the car just has no power, and I'll have to downshift to 4th or even 3rd just to maintain my speed. During these moments, the engine note also takes on a different character where even at 3,000 rpm on level ground or going downhill it sounds bogged down like I'm driving through molasses. If I let off the gas completely while in gear, the car slows down like I'm dragging an anchor, even in 6th. 1st - 3rd gear generally feel normal, though I notice the car does tend to tip into boost with less throttle than usual. When I am experiencing the power loss, the MFD gauge will register my throttle inputs as normal, and the engine will still build boost, just with no increase in power output.
Now, I understand that air becomes less dense at higher elevations, but this usually gives turbo cars an advantage over NA engines. I should also make it clear that I am not trying to climb steep hills in 6th gear at 2,000 rpm. In fact, I mainly experience this power loss traveling downhill, and it seems to occur most often through rolling hills where I am constantly changing elevation. This only happens in the mountains, and occurs independent of outside temps or climate control settings. The power loss will sometimes last several miles, then may clear up for a time before returning. I experience no issues or loss of power elsewhere. I was wondering if anybody else has had a similar experience with the FA engine? Is this just normal behavior for the stock tune as it adjusts to changes in elevation? Or am I simply experiencing the effects of thinner air at higher elevations? Any help or input would be very much appreciated!
* Registered users of the site do not see these ads.
|
07-20-2021, 11:39 PM | #2 |
Scooby Specialist
Member#: 472037
Join Date: Jul 2017
Chapter/Region:
MWSOC
Vehicle:2018 WRX Limited CWP |
I live in Colorado and my 18 is perfectly fine up and down the mountains.
I don't think its a normal behavior but do check your air filter. The opening for the airbox scoop is directly open to front bumper and at 30k miles mine was filled with leaves and bugs. Maybe yours is heavily blocked unable to allow the engine to breath. |
07-21-2021, 12:57 AM | #3 |
Scooby Newbie
Member#: 446029
Join Date: May 2016
Location: 510
|
Without the ability to monitor or data log it's hard to say.
Maybe its getting heat soaked. The intake temperatures are getting high and making the car pull boost and timing. What is the weather like when this happens? |
07-21-2021, 10:13 AM | #4 |
Scooby Newbie
Member#: 525654
Join Date: Jul 2021
Location: Long Island, NY
Vehicle:2019 WRX WRB |
That’s what I thought the first time it happened, as temps were in the mid 90s. However, I have taken trips with outside temps in the mid 50s - 70s with the same result. Additionally, it happens mostly when I’m moving pretty fast on the highway, where there is more airflow and I would think heatsoak would be less of a concern. Can’t view intake temps without an A/P, but oil temps are well within normal (205 to 212) and no change on the dummy coolant gauge.
|
07-21-2021, 10:14 AM | #5 | |
Scooby Newbie
Member#: 525654
Join Date: Jul 2021
Location: Long Island, NY
Vehicle:2019 WRX WRB |
Quote:
|
|
07-21-2021, 12:10 PM | #6 | |
*** Banned ***
Member#: 500337
Join Date: Apr 2019
|
Quote:
Does it rain when this happens? Any constants you notice weatherwise or circumstances-wise while in these up/down mountainous hills? |
|
07-21-2021, 12:32 PM | #7 | |
Scooby Newbie
Member#: 525654
Join Date: Jul 2021
Location: Long Island, NY
Vehicle:2019 WRX WRB |
Quote:
|
|
07-21-2021, 12:59 PM | #8 | |
*** Banned ***
Member#: 500337
Join Date: Apr 2019
|
Quote:
No AccessPort? Id monitor tgv and egr operations at those inputs and those ranges when it usually happens but dont know how youd do it if you have no AP. Anyone have suggestions? My suggestion is dont go downhill in 5th at 2-3000rpm. But that is coming from someone who drives in 3000-5500rpm range 99% of time. I downshift to be at 3000rpm+ at any given moment in time. Going downhill id be in a gear which is somewhat breaking my acceleration so probably 35-4000rpm range, same goes for uphill, id stay 35-4000+ range and the modulate throttle. If nothing else i would try it to see if it is tune related at that rpm and load request. |
|
07-21-2021, 02:18 PM | #9 | |
Scooby Newbie
Member#: 525654
Join Date: Jul 2021
Location: Long Island, NY
Vehicle:2019 WRX WRB |
Quote:
|
|
07-21-2021, 03:20 PM | #10 | |
*** Banned ***
Member#: 500337
Join Date: Apr 2019
|
Quote:
Does it bog down in all those instances? I still think you are experiencing an egr and tgv tune related issue with light throttle and no load basically (going downhill) so car goes into egr mode. I am not a tuner but i would suspect it would not go into same mode with higher rpm, like 45-5000+, thus lower gear works. |
|
07-21-2021, 03:30 PM | #11 | |
Scooby Newbie
Member#: 525654
Join Date: Jul 2021
Location: Long Island, NY
Vehicle:2019 WRX WRB |
Quote:
What I’m wondering is why this would occur with the stock tune. Surely Subaru has tuned the car to adjust to variances in elevation, air density, temperature, etc… I have been too afraid to really lay into the throttle when the car gets sluggish like this, since the engine sounds like it’s lugging. This cannot be the case, however, as I don’t think the car would lug with light throttle at 3,000 rpm in any gear, especially going downhill. It’s really like the ecu just doesn’t know what to do with the changes in elevation, and downshifting to a very high rpm “wakes the car up,” so to speak. At least this is what it feels like from my perspective as a driver. |
|
07-21-2021, 06:08 PM | #12 |
Scooby Specialist
Member#: 419593
Join Date: Apr 2015
|
It is the stock mapping. The stock tune loves to pull timing.
|
07-22-2021, 08:41 PM | #13 |
Scooby Newbie
Member#: 518233
Join Date: Aug 2020
Vehicle:2019 WRX |
i think your secondary turbine stopped spooling or someting
|
07-26-2021, 02:47 PM | #14 | |
Scooby Newbie
Member#: 461015
Join Date: Jan 2017
Location: Littleton, CO
Vehicle:2017 WRX |
Quote:
|
|
07-27-2021, 10:50 PM | #15 | |
Scooby Specialist
Member#: 472037
Join Date: Jul 2017
Chapter/Region:
MWSOC
Vehicle:2018 WRX Limited CWP |
Quote:
|
|
07-28-2021, 05:12 PM | #16 |
Scooby Newbie
Member#: 425326
Join Date: Jul 2015
Chapter/Region:
NESIC
Location: Colchester, CT
Vehicle:2016 WRX Pearl White |
With all due respect to our wonderful NASIOC brothers that have graciously offered their time and opinions on your specific issue; I strongly suggest to IGNORE their input due to their obvious overall inexperience with TUNING the FA20DIT motor or any Subaru motor in general. This is NOT to diesrespect their offerings but only to pinpoint the actual cause of the boost "leak" as it has been presented by the owner. I have several additional questions to the SubiPsy (owner) to ask to pinpoint the actual cause of what I believe is a vacuum leak. If you want my input please reply.
|
07-29-2021, 05:56 PM | #17 |
Scooby Specialist
Member#: 424203
Join Date: Jun 2015
Chapter/Region:
NWIC
Location: Boston, MA
Vehicle:2016 WRX STage ?? Dirty |
Probably some sisters on here too.. such a man splainer! Lol .. We need logs to identify if AFR targets are out of wack.. what kind of A/F Learning 1 # do you have ( then we can prove a leak quite easily ) going up a hill in 5th gear 3k or under is not wise! These are not low end torque engines. That is asking for free engine block windows! Btw power can't be measured by "a feeling" my car at 300whp felt way faster because of how boost came on.. my 550whp setup is way faster but is smooth as butter (to ur butt it feels slower) .. my 2 cents, get a data log check the #s .. it could be a variety of things.. but it feels more like a good case of engine lugging, heat soak and bad driver..
|
07-29-2021, 06:04 PM | #18 | |
*** Banned ***
Member#: 500337
Join Date: Apr 2019
|
Quote:
|
|
07-29-2021, 08:20 PM | #19 |
Scooby Specialist
Member#: 424203
Join Date: Jun 2015
Chapter/Region:
NWIC
Location: Boston, MA
Vehicle:2016 WRX STage ?? Dirty |
Yeah makes no sense to have been happening the last 3 years only in the mountains??? I used my subie for hill climbs.. climbed every mountain in the PNW without a hiccup in 100+ to -35 degrees weather.. My problem is overheating and blowing out rear ends!!
|
07-30-2021, 12:31 AM | #20 |
Scooby Specialist
Member#: 472037
Join Date: Jul 2017
Chapter/Region:
MWSOC
Vehicle:2018 WRX Limited CWP |
I guess the theory is in the mountains when the air pressure is lower, your turbo works harder more close to it's theoretical limit with less spare pressure to give thus lower max boost.
I do know my WRX has not hit higher than 19 max psi where on flat land I hit more than 21. |
07-30-2021, 10:14 AM | #21 | |
*** Banned ***
Member#: 500337
Join Date: Apr 2019
|
Quote:
|
|
07-31-2021, 08:50 PM | #22 | |
Scooby Specialist
Member#: 472037
Join Date: Jul 2017
Chapter/Region:
MWSOC
Vehicle:2018 WRX Limited CWP |
Quote:
|
|
Thread Tools | |
Display Modes | |
|
|