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Discussion Starter · #1 ·
I just got an 01 IS300 auto and have a quick question abour a weird trans behavior. When accelerating moderately(and it has to be juuust right), when the trans goes to shift from second to third this happens: The car stops accelerating, revs stay at roughly 5k, it pauses there for a second, then shifts hard into third and i'm off again.

It only does this at a very specific throttle position that i have not yet been able to duplicate on a regular basis. I'm planning on changing the trans fluid soon, but it seems to be a computer issue as it doesn't slip or anything, its like the engine is cut off from fuel, then it slams into third and i'm off like normal.

Thanks for any help you guys can give, worse case scenario i'm not even that concerned as i've seen several auto trans for these cars go for under 500 bucks(WAAHOO!!, comapred to the 3-4k my audi's would have cost).

Look forward to being a contributing member of this board,
Ryan
 

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How many miles? Clean your MAF and change your fluids like you said.

My car at 60K was not as buttery smooth as it used to be, and then I changed the tranny and diff fluid, and it is like brand new!
 

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Discussion Starter · #3 ·
i'm assuming MAF is mass air flow sensor? Anyone know where to get a good repair manual for this particular car? I dont recall if bentley offers one for this car...
 

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Discussion Starter · #5 ·
sweet! Thanks for the link. Downloading it right now. Will do a little more searching next time;)
 

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Sounds like your tranny is sliping. Could be that you need new fluid or a synchro or gear is worn.
 

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Discussion Starter · #7 ·
Sounds like your tranny is sliping. Could be that you need new fluid or a synchro or gear is worn.
It doesn't slip, though. It just takes a while to change to the next gear, and while it waits it stops accelerating in second gear.. It goes up to 5k, sits there, and then shifts hard into third, but there is no slippage of any kind, in second or third gear. I'm wondering if it isn't something i'm doing, like taking off harder and then subconsciously lifting off the gas as i reach the speed i'm trying to go, and the computer doesnt know what i'm doing so it delays.

I'm going to read up and try to figure out how to reset the drive by wire system, maybe that will help?
 

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my first thought was the same as a few others... clean your maf and possibly a reflash of the ecu
 

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It doesn't slip, though. It just takes a while to change to the next gear, and while it waits it stops accelerating in second gear.. It goes up to 5k, sits there, and then shifts hard into third, but there is no slippage of any kind, in second or third gear. I'm wondering if it isn't something i'm doing, like taking off harder and then subconsciously lifting off the gas as i reach the speed i'm trying to go, and the computer doesnt know what i'm doing so it delays.

I'm going to read up and try to figure out how to reset the drive by wire system, maybe that will help?
You can reset the ECU by unpluging your battery.
 

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Discussion Starter · #10 ·
thanks. Its actually gotten alot better the more i drive the car. It hasn't done it in a couple of days now, i don't know if i've just gotten used to it and know how to drive it so it doesn't happen, or if the car has learned my driving style. I imagine while sitting on the dealers lot it was romped on during test drives, so the computer probably made adjustments for that and it just took time to get used to my more conservative style.

I'll reset the computer tomorrow just to make sure. Thanks for all the help guys,
Ryan
 

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I think the fly by wire system in this car sucks. Plus there is a computer update for the ECU that I believe is for harsh shifts. Can't remember exactly what the TSB says. It's finicky though I know that. Probably the worst thing about the auto in my opinion.
 
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