Hi folks, I posted before about how after I had to brake very hard to prevent a collision my car started feeling different - after that I replaced the front LCA bushings, front shocks, and most recently the three engine/tranny mounts.

I no longer have vibrations in neutral, and overall things seem a bit tighter but I am still having the same issues that started after my near-collision:

1. a momentary 'clunk' that I FEEL more than hear, when shifting R>D or D>R
2. momentary lag when the car is upshifting at low speed, feels like it won't respond then surges forward
3. momentary lag or engine brake feel when the car downshifts - basically, shifts are more noticeable, particularly at lower speeds
4. before the car seemed to coast better when I let off the gas, now it feels like it engine brakes more

I was wondering whether to try to go after the rear differential bushings - it seems like a lot of labor.

I was ALSO wondering if maybe this is the onset of that ECU/ECM? issue? I have read a few threads about the computer chip issue but what I haven't seen is anyone talking about how the issue started for them. Does it start slowly, or is it all of a sudden there? Not sure how really hard braking would cause it, which is why I thought it was related to mounts/bushings in the first place, but I'm a little discouraged after not seeing it get significantly better with the new mounts.

 

Have you checked the trans fluid? This happened on an old Honda I bought and the trans fluid hadn't been flushed in forever. Fixed it right up.

Otherwise yeah my next best guess would be something to do with the ecu. These types of issues are almost never what you think it would be.

I'm new to the LS/Toyotas in general but maybe you could just buy a low mileage ECU and have a tuner match it to your VIN? I bet Quantum Auto could sort you out with that.

 

this sounds similar to how my LS drives, from what i've read it sounds like its an ecu problem. quantum auto or sia electronics are two places that do ecu work. though I emailed sia inquiring about it and they never responded

at high speeds the problem is nonexistent, but low speeds it'll act exact like you stated. shifts feel awful.

 

I don't want to overstate the problem, it's mild compared to what everyone online seems to complain about... There's just a bit of 'lag' in the response, or in gear shifts. No clunks/thuds during gearshifts.


I was thinking about doing a drain/fill x3, as is the SOP for this car. It only has 80k miles. I did change the rear diff fluid and it was pretty bad - smelled burnt. I've wondered whether I screwed something up when I changed the rear diff fluid but I don't think so.

But again, does the ECU problem come on all of a sudden? Is it gradual?