Hi GR86 forums,
BRZ 2023, 25k km, single owner. I have an issue where the throttle body is opening and closing by itself without any throttle being applied. Please see this video: https://photos.app.goo.gl/9miRReWEpWxLd7qr8
In the video, I'm rolling, then letting off the gas, pushing in the clutch, and going on the brakes as you can see from the left of the dash. The RPMs will rise to 2500 RPM before falling back to normal idle.
This can happen with varying intensity. Sometimes it will not happen, and other times it will go to 3000 RPM, fall back down to 1500, climb back up to 3k RPM a couple times before idling normally.
This behaviour is obvious when you push the clutch down since you'd expect RPM to drop. But I think it's happening even when I'm driving. It's more subtle but I feel it most when I'm driving slow between 20 and 30 kph (think traffic scenario). The car will jerk back as if I pressed on the throttle, and then jerk to the front as if I suddenly let go and it's engine breaking.
This weird behaviour will stop as soon as you go to neutral. Only happens when you're in gear.
It seems like it's also temperature dependent. After a cold start, it will no do it for a few minutes. When I'm in traffic, or stuck in a drive-thru for example, it will be the most drastic.
I have been to the dealership many times. I have also been to a private mechanic specialized in Subarus. They say there's nothing wrong mechanically with the car (no error codes, sensors are all good, no vacuum leaks, throttle body is clean, etc.). I've gotten conflicting information from Subaru dealership: they noted the behaviour, but they didn't know how to correct it so they've been in contact with the Subaru Tech-line. Subaru Tech-line says they're had this issue with the Crosstrek manual before, and that it was solved with an ECU update. No such update yet for BRZ, and no timeline. After pushing them for a while, they're now saying Tech-line has compared this behaviour with another BRZ on their side, and it's normal behaviour. So it seems they don't think there's a problem, they're not working on an update. But they were also saying when an update will come it will solve my issue (conflicting info...). I've also sent a letter to Subaru Canada, but all they did was refer me to the dealership.
The private mechanic was baffled at that. He says it must be programming. He showed me telemetric reading of the throttle body opening and closing by itself after he let off gas and pushed in the clutch. He's saying only Subaru can solve that, unless I'm willing to install an aftermarket tune (but I want to keep my warranty).
I've already posted about this issue on the forums before, but none of the suggestions solved it. So if anyone has any other suggestions please let me know. Sorry for the wall of text, but I wanted to write a detailed description.
I'd also like some advice on what to do moving forward to force Subaru to fix my car. I don't have social media to put any pressure on them. I think my next step is to write a legal letter?
Thank you!
BRZ 2023, 25k km, single owner. I have an issue where the throttle body is opening and closing by itself without any throttle being applied. Please see this video: https://photos.app.goo.gl/9miRReWEpWxLd7qr8
In the video, I'm rolling, then letting off the gas, pushing in the clutch, and going on the brakes as you can see from the left of the dash. The RPMs will rise to 2500 RPM before falling back to normal idle.
This can happen with varying intensity. Sometimes it will not happen, and other times it will go to 3000 RPM, fall back down to 1500, climb back up to 3k RPM a couple times before idling normally.
This behaviour is obvious when you push the clutch down since you'd expect RPM to drop. But I think it's happening even when I'm driving. It's more subtle but I feel it most when I'm driving slow between 20 and 30 kph (think traffic scenario). The car will jerk back as if I pressed on the throttle, and then jerk to the front as if I suddenly let go and it's engine breaking.
This weird behaviour will stop as soon as you go to neutral. Only happens when you're in gear.
It seems like it's also temperature dependent. After a cold start, it will no do it for a few minutes. When I'm in traffic, or stuck in a drive-thru for example, it will be the most drastic.
I have been to the dealership many times. I have also been to a private mechanic specialized in Subarus. They say there's nothing wrong mechanically with the car (no error codes, sensors are all good, no vacuum leaks, throttle body is clean, etc.). I've gotten conflicting information from Subaru dealership: they noted the behaviour, but they didn't know how to correct it so they've been in contact with the Subaru Tech-line. Subaru Tech-line says they're had this issue with the Crosstrek manual before, and that it was solved with an ECU update. No such update yet for BRZ, and no timeline. After pushing them for a while, they're now saying Tech-line has compared this behaviour with another BRZ on their side, and it's normal behaviour. So it seems they don't think there's a problem, they're not working on an update. But they were also saying when an update will come it will solve my issue (conflicting info...). I've also sent a letter to Subaru Canada, but all they did was refer me to the dealership.
The private mechanic was baffled at that. He says it must be programming. He showed me telemetric reading of the throttle body opening and closing by itself after he let off gas and pushed in the clutch. He's saying only Subaru can solve that, unless I'm willing to install an aftermarket tune (but I want to keep my warranty).
I've already posted about this issue on the forums before, but none of the suggestions solved it. So if anyone has any other suggestions please let me know. Sorry for the wall of text, but I wanted to write a detailed description.
I'd also like some advice on what to do moving forward to force Subaru to fix my car. I don't have social media to put any pressure on them. I think my next step is to write a legal letter?
Thank you!
