Help! 18 wrx-Sometimes while driving car does nothing for a split second

[hellosunshine]

Sometimes while driving at a consistent speed my car does nothing for a split second. It feels like I'm letting off the gas when I am not and when I go to floor it nothing happens during that down time and then the car comes back to life. No check engine light, no lurching, no rough idle its like nothing ever happened and the car just doesn't respond to the gas pedal for a second or two.



I have a 18 wrx-manual- 84k mi. When I bought the car it came with a cobb cold air intake and I think an axle back.



I had a lean code and thought maybe this was causing the "limp" mode but I think this is a whole different issue. (I think it was a p0171 code)

Spark plugs were done 20 k mi ago.

Within the last 2 months Ive replaced the MAF, downstream O2 sensor, throttle body and the gas pedal. I even bought a COBB access port and tuned the car to the stage 1 big sf.



I tried taking it to the dealership but they said because its modded they wouldn't even look at it. Ive been taking it to Goodyear and they cant find anything either.


Any help would be greatly appreciated! I have never owned a Subie and love my car but dont know what else to do. I got a 5 min snap shot while cruising of a data log where it actually happened! I am hoping this helps and I'm wondering if someone knows anything about these logs and can see if anything looks weird? I have no check engine light or any other weird symptoms. This is very intermittent but its starting to happen more and I am getting a little nervous regarding safety. I highlighted in yellow where im "flooring it" but nothing is happening. line 3638- 3649. https://docs.google.com/spreadsheets/d/1g5DJVDrVLErwK4UX9HV1Uj9-8jd9sGY3udaU2U2P9fU/edit?usp=sharing


Thank you!!!!

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[hellosunshine]

-update-
still no luck. Bought a new pedal from dealership. When installing it unplugged battery put new pedal in. I dont drive my car much. Honestly Kind of scared to now. Went on a few chill drives and nothing happened over the last week. Went for a drive tonight, got gas and pedal went out again on way home. (while driving feels like I let off the gas pedal when I didnt) I started the log as soon as there was no response with the pedal to the floor with nothing happening. I believe it came back around line 175 because thats when I see 100 for the Accel Position (%) and the speed started going back up. Everything I've searched and have seen people with similar issues but no resolutions. Any help would be greatly appreciated.



https://docs.google.com/spreadsheets...it?usp=sharing

[hellosunshine]

Update: lots of money later, It was a brake light switch..Problem gone.

[hellosunshine]

JK, going to update this again with my final post because the problem came back, but it is fixed!!!!

After countless hours of replacing things one by one that technically could cause the issue, talking to the dealership, taking it to a performance shop, and literally having a boyfriend who has been a mechanic for over 20 years, no one could figure this out. Even here, no answers. Most people looked at me like I was crazy when I was describing this issue so I hope whoever is reading this and is having this issue has a good place to start, and it fixes their issue without needing to spend tons of money for no advise or help.

After lots of digging online for answers and many tears of frustration, it was my F1 brake light.....(good ole reddit comments btw =FREE) I disconnected it 4ish months ago, and the problem is gone. I am back to driving on long trips and around town without the pedal going dead....

I am not a mechanic, but when I think about it logically, my thoughts are that something with the F1 brake light was telling the car I was braking, which may have been sending a signal to the computer, which was causing the VDC light to come on, thinking that I was maybe losing control of my car when I wasn't, which was stopping power to the pedal for safety reasons.

My advice to anyone going through this issue would be to start with disconnecting the F1 brake if you have one and possibly replacing the brake light switch. Don't go down a checklist of replacing things and going to dealerships and shops that are just going to try to take all your money and not even know how to fix it. Something literally this simple and problem solved.

[GoFrogs]

Originally Posted by hellosunshine

My advice to anyone going through this issue would be to start with disconnecting the F1 brake if you have one and possibly replacing the brake light switch. Something literally this simple and problem solved.

Glad you solved the problem. What brand brake light was it?

Did you leave light in and only run it as a rear fog; or removed it completely?

I have a Vinstar light (3 rows x4 LEDs) [one of the cheapest lights on the market] and only use it as a rear fog. I left the blinking brake light disconnected from day one so I'm guessing I should be okay.

[hellosunshine]

Originally Posted by GoFrogs

Glad you solved the problem. What brand brake light was it?

Did you leave light in and only run it as a rear fog; or removed it completely?

I have a Vinstar light (3 rows x4 LEDs) [one of the cheapest lights on the market] and only use it as a rear fog. I left the blinking brake light disconnected from day one so I'm guessing I should be okay.

After some research and them all appearing to be the same I seen someone say "All f1 lights come from the same company and factory in China and that there is no difference in quality from Subispeed & Subibros to Ebay. They are identical and all the same units so I got this one off Amazon and it lasted 2 years 5 months " https://www.amazon.com/gp/product/B08R5H8TL4?ie=UTF8&th=1" I disconnected it all together. Is your subi doing the same thing where the gas pedal just stops working?