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AT not downshifting on hard stops

AT with 80,000 miles running 225 Bridgestone S-04s and Project mU HC+800 pads. ATF has been replaced twice and level is checked and good.

When coming to a hard stop (first noticed when someone stopped quick on a yellow in front of me) my car stalled. Since then I have tried replicating the issue and have been able to get the car to stall or at least bog RPMs due to not downshifting into 1st gear. If it bogs only when I go to accelerate th e car kicks into gear super hard.

I am not able to replicate this on stock wheels and brakes exactly minus a very slight RPM stutter that occurred once in 5-6 attempts.

My question is has this occurred on anyone else's AT? Is this an issue of the car getting confused from the hard stop or something wrong? It only occures on complete stops, if I ease off the brake a little at the end it won't do it.

Anyone else experience this or mind attempting to replicate this? Have a 100k mile warranty and trying to decide if I need to fight with Toyota on it (went in once and they couldn't find anything, blamed it on my OBD Bluetooth that I forgot was plugged in)

TIA

Make sure your car has this TSB done one is ECU firmware your ecu firmware should be ZA1JB01D if it was a pre 2014 car

S-SB-0040-13 : Intermittent RPM Drop

Quote:

Originally Posted by steve99 (Post 2409986)

Make sure your car has this TSB done one is ECU firmware your ecu firmware should be ZA1JB01D if it was a pre 2014 car

S-SB-0040-13 : Intermittent RPM Drop

I'll look in to it. However, the rpms only dips on deceleration not at idle. And it happens with the AC on and off.

Quote:

Originally Posted by finch1750 (Post 2410857)

I'll look in to it. However, the rpms only dips on deceleration not at idle. And it happens with the AC on and off.

Their was about 3 "fix's" for idle dips . rough idle ect these were A00D A01D(also incorporated DI seal fix transient retard) B00D and B01D.

B01D will have all previous "fix's". They still have a couple of idle problems.

Most tuners will bump idle to 750 and may also modify the DI/PI injection tables to run full DI at idle.

My car (although it manual G rom) still did the occasional idle dip on deceleration comming to a stop with clutch in till I changed the DI/PI injection tables to run full DI at idle

One last bump for any other thoughts

steve99 sounds like he knows what he's talking about. something ecu related. if not then maybe the torque convertor?