'14 GT86 6AT issue in Manual Mode

[Gamabouy]

I have a 2014 Toyota 86 with an automatic trans that I got about 3000 miles ago. The car runs quite smoothly in D without any issues. But I have noticed the transmission acting up randomly at times where it would hesitate when in manual mode. This does not happen all the time but frequently.

I have already changed the air filter, cleaned the throttle body, replaced the battery (re-calibrated the throttle position) and used a fuel injector cleaner.

This hesitation is there even in sport mode, and it occurs also when I use the paddles in D. Going back to D and letting the car shift on its own is the only way out of it.

Below is a video of it first being in manual mode and then in automatic mode, both of them are in WOT (pedal depressed fully). Notice how slow it is in M mode but is way faster in Automatic (D).

Also, the speed is in kph.

I am aware there is a TSB for the TCM but I don't have the stalling issues prescribed and I am fairly certain the dealership would not be willing to flash the TCM for me.


UPDATE: It seems to have been an injector issue, I have booked for the seals to be replaced and will update accordingly. Looks like the ECU uses DI more in manual or something which is why there is so much hesitation.

[fitcious]

I don’t know what’s wrong but it seems like your display is displaying the wrong gear when in M mode (displays 2nd when it is actually in 4th). Seems like you’re in 4th gear or so when accelerating. While in D, it downshifts to actual 2nd gear.

[Gamabouy]

I tried downshifting and upshifting, it did so without issues. I am pretty certain they are on the respective gears.

The issue is only apparent and persists when I go into M mode. Else the car drives pretty smoothly.

[tarzan_nojane]

If there is no record of the AT fluid being drained and flushed, it is something serious to consider after 60,000 mi (100,000 km). There is a fairly elaborate procedure just to get the correct fill level.

[OwlDance]

In drive mode when you floor it, the car is automatically downshifting to first gear - which does not lock up so it downshifts very quickly. When you're driving in manual mode, the trans if fully locked up, and if you're flooring it at 2k RPM and you're basically lugging it. Tip, don't floor the car below 3K RPM or else you're putting a ton of strain on the engine, and don't floor it in higher gears until you're higher in the RPM too (barring emergencies of course.)



I don't see anything wrong here otherwise.

[Gamabouy]

Originally Posted by OwlDance

In drive mode when you floor it, the car is automatically downshifting to first gear - which does not lock up so it downshifts very quickly. When you're driving in manual mode, the trans if fully locked up, and if you're flooring it at 2k RPM and you're basically lugging it. Tip, don't floor the car below 3K RPM or else you're putting a ton of strain on the engine, and don't floor it in higher gears until you're higher in the RPM too (barring emergencies of course.)



I don't see anything wrong here otherwise.

Thanks for the reply. I figured that's what was happening once I tried it again a few times. The hesitation seems to have gone when I refilled gas from a different place too (I hope).

As for your last comment, is it better for the engine's life to always use the first gear until I am at a high enough speed then to shift into second? or is this only when I want to floor it and accelerate quick? The car likes to shift into 4th gear before even hitting 60mph (casual driving, not WOT) so I assumed it was better for the engine to sit at low rpms.

[OwlDance]

Generally it depends on the load but yeah it's better to keep the RPMs low within a limit. It's basically like driving a manual car, low RPMs (to a certain point) are better. If you're driving in automatic mode I would let it do its thing by itself for a lot of complex reasons, but basically until 4rth gear its spinning a torque converter fluid coupling which reduces engine strain at those very low RPMs. As a side note I don't really use manual mode until after 10 minutes after I start up the car to let it warm up because it requires higher RPM which is a bit harder on the engine until its warm (although you're dubai so I assume it warms up pretty quickly regardless).

In manual mode (which functions like sport mode) the trans locks up so you have to shift it like a manual - I would cruise around 2-3.3k RPM on manual mode, which allows you to shift and keep the following gear within the 2-3k range. I personally would not use first gear for full power and would rather be gentle until above 3k in second. But I like to shift 1st gear around 3-4k RPM if I'm going from a standstill like a stop light before a long road, so second binds up around 2K RPM and just above lugging range.

If you need to accelerate quickly in manual mode however definitely downshift if you can.