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Discussion Starter #1 (Edited)
I have a PFS race built tranny with a Dragon 3200 TC, and about 30% of the time when the car shifts at low rpm, the rpms will drop to about 1300 and stay there for about 2 seconds regardless of what I do with the gas pedal, then the power will kick back in. The delay occurs the second the 1-2 shift occurs, I thought it could be a MAF issue so I swapped MAFs and that didn't help. Unplugged the battery and still does it.

Anyone have an idea? Is it mechanical or electrical? I know there are 2 service bulletins for the 01 Auto IS for ECM calibrations but they are for harsh 2-3 shifts and throttle response/downshift quality, none for 1-2...

It is getting kind of serious because it is becoming a safety issue and the dealer also doesn't know what the problem is....what a waste of $100...

Any help would be appreciated, thanks.
 

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I have a PFS race built tranny with a Dragon 3200 TC, and about 30% of the time when the car shifts at low rpm, the rpms will drop to about 1300 and stay there for about 2 seconds regardless of what I do with the gas pedal, then the power will kick back in. The delay occurs the second the 1-2 shift occurs, I thought it could be a MAF issue so I swapped MAFs and that didn't help. Unplugged the battery and still does it.

Anyone have an idea? Is it mechanical or electrical? I know there are 2 service bulletins for the 01 Auto IS for ECM calibrations but they are for harsh 2-3 shifts and throttle response/downshift quality, none for 1-2...

It is getting kind of serious because it is becoming a safety issue and the dealer also doesn't know what the problem is....what a waste of $100...

Any help would be appreciated, thanks.
i think i know what you mean, like after the 1-2 goes and you shift to 3, but at low rps it seems the car loses power for like a split second then the rpm goes back up right?

this problem or i dont know even if its a problem but for me i just press the gas pedal a little harder then it wont do it, but only when and if i go slow and shift under 2krpm it will do that.
 

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Discussion Starter #3
It seems to do it at anything below 3k rpm, but it will occur mostly at rpms below 2k. The problem is not when I click to 3rd, the 2-3 shift is fine, it is the 1-2 shift.
 

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It's just the way it is unfortunately... I assume the shift schedules for the stock automatic for low speed 1-2 shift is purposely closing the throttleplate to avoid jerking or rough shifts. Somehow the built transmissions upshifts from 1-2 a little too fast, and the ECU doesn't know how to compensate somehow...

If you notice on your stock transmission, the 1-2 gear shift is really soft and slips a lot. The throttleplate has already closed in most cases, but you don't physically feel the car "bog down" like with the built transmission.

I had the exact same problem that you have for the longest time already, especially when I am about to make a left hand turn at a large intersection and easing into the throttle while going into the turn.. Suddenly, the car would just bog when going from 1st to 2nd, lose power (and won't budge even if I floored it), and hesitate for a second or so, and then resume its power.

I have tried everything to combat this problem, and the best thing I could do was blip the throttle deeper if I were ever making a left turn.. By blipping the throttle deeply at initial acceleration, the transmission would tend to shift from 1st and quickly into 2nd and immediately upshift to 3rd and prevent it from happening.

I noticed that this was not an electrical or mechanical problem, because as you heard, I swapped back to my stock transmission not too long ago because my TE built race transmission took a crap. The moment I swapped back to the stock transmission, the problem was gone, but I can still hear and feel the engine doing the same "shut off" thing, but yet the car doesn't bog like with the built trans.

If you find a solution, let me know as well because I am putting back in the repaired built trans sometime around spring... I would love to have this problem fixed too.


Hope this helps :)
 
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I bought a turboeast racebuilt tranny, I don't seem to have this issue at all. But I do remember them saying that they did something to the 1-2 shift and that only a few places know what it is, or how to do it. I wonder if that deals with the issue your talking about.
I know turboeast is closed, but the guy who built their trannies there is still doing it. Maybe look him up and ask him.
 

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Discussion Starter #6
I bought a turboeast racebuilt tranny, I don't seem to have this issue at all. But I do remember them saying that they did something to the 1-2 shift and that only a few places know what it is, or how to do it. I wonder if that deals with the issue your talking about.
I know turboeast is closed, but the guy who built their trannies there is still doing it. Maybe look him up and ask him.
Only a couple places drill out the 1-2 shift to actually make it shift faster, all the other gears use accumulator rods, that is what TE was talking about, they weren't talking about the actual problem that occurs when the 1-2 shift is drilled....
 

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I have tried everything to combat this problem, and the best thing I could do was blip the throttle deeper if I were ever making a left turn.. By blipping the throttle deeply at initial acceleration, the transmission would tend to shift from 1st and quickly into 2nd and immediately upshift to 3rd and prevent it from happening.
This is what i do so i dont get that "bog"


TE built race transmission took a crap.
What were ur #'s before it went out?



I bought a turboeast racebuilt tranny
What is ur #'s right now ?
 

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Would the physical difference of the different means of making the shift faster been seen differently by the car's computer/sensors? Thats the best explanation I can think of for some peeps not having the problem, and some others having it.

Sounds like with the problem, the car still thinks its shifting when the shift has far been over with. The others, the car is in the loop were the tranny status really is and the DBW acts accordingly. An easy electrical fix isn't coming to mind for this, maybe the old'school TE ESK?
 

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Discussion Starter #10 (Edited)
maybe ummm call pfs?
You're a true value to this site :rolleyes: , of course I have called Ray on the subject.


EDIT- I actually reved the car up pretty hard to about 3200 rpm today and it still bogged, so this is getting messed up....Ray seems to think it is something with the throttle plate/throttle input, nothing mechanical, but he doesn't really know.
 

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You're a true value to this site :rolleyes: , of course I have called Ray on the subject.


EDIT- I actually reved the car up pretty hard to about 3200 rpm today and it still bogged, so this is getting messed up....Ray seems to think it is something with the throttle plate/throttle input, nothing mechanical, but he doesn't really know.
and what did ray say? ;)
 

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This is what i do so i dont get that "bog"

What were ur #'s before it went out?
The power numbers were always between 340-380 WHP, with a few exceptions to higher boost mode (1-2 psi more) which puts it a little over 400WHP at most.

The day the transmission went was actually at normal boost mode, 370ish WHP.
 

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What is ur #'s right now ?
I'm just over 400 rwhp as well. I've had the tranny in now for about 2 months, and I have a Level 10 tc in it. This month I'm going to put a tranny cooler on and up the line pressure.
 

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Would the physical difference of the different means of making the shift faster been seen differently by the car's computer/sensors? Thats the best explanation I can think of for some peeps not having the problem, and some others having it.

Sounds like with the problem, the car still thinks its shifting when the shift has far been over with. The others, the car is in the loop were the tranny status really is and the DBW acts accordingly. An easy electrical fix isn't coming to mind for this, maybe the old'school TE ESK?
Yeah, this was my thinking as well. That whatever they do to the tranny for the 1-2 shift acts like the correct response for the sensors. So the car responds correctly.
I went out tonight to try and simulate the issue as described, and the car never lagged in response or bogged at all. I did a 15 mph roll and let off the gas to allow the car to slow down to about 5 mph and made the turn and gave it gas and the car shifted as needed and responded on time. So, I guess I'm wondering if altering or whatever it they do to the 1-2 shift is the answer. I would call Turboeast and ask him. See what he has to say about it anyway.
 

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Discussion Starter #17
Yeah, this was my thinking as well. That whatever they do to the tranny for the 1-2 shift acts like the correct response for the sensors. So the car responds correctly.
I went out tonight to try and simulate the issue as described, and the car never lagged in response or bogged at all. I did a 15 mph roll and let off the gas to allow the car to slow down to about 5 mph and made the turn and gave it gas and the car shifted as needed and responded on time. So, I guess I'm wondering if altering or whatever it they do to the 1-2 shift is the answer. I would call Turboeast and ask him. See what he has to say about it anyway.
Turboeast is a Starbucks now, PFS is who built my tranny and Ray really has no idea what the problem is. My car is now doing it around 30% of the time regardless of throttle input, however, it does it more when the car/tranny is cold, which worries me because that makes it sound like it is mechanical....
 

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Yeah, I know they are closed, but the guy that built all the trannies for TurboEast is still building them.

I know PFS knows what they are doing also though. I have talked to Ray before. Really nice guy. I'm sure if he had the car in front of him they would figure it out.
 

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Discussion Starter #19 (Edited)
Yeah, I know they are closed, but the guy that built all the trannies for TurboEast is still building them.

I know PFS knows what they are doing also though. I have talked to Ray before. Really nice guy. I'm sure if he had the car in front of him they would figure it out.
I know, but i'm on the other side of the country :curses:


Anyone think a complete ECU/ECM system reflash by the dealer would do anything?
 
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