Problems upshifting
Enough of the useless side banter..
BACK ON TOPIC..
Has anyone else had any type of issues with upshifting from 4th to 5th while at WOT? Lexus Corp and my local dealership are still researching to see if anyone else is having this issue.. I am actually half-tempted to remove the headers and exhaust from my car to see if that has anything to do with it, but I am just unclear as to how it would..
BACK ON TOPIC..
Has anyone else had any type of issues with upshifting from 4th to 5th while at WOT? Lexus Corp and my local dealership are still researching to see if anyone else is having this issue.. I am actually half-tempted to remove the headers and exhaust from my car to see if that has anything to do with it, but I am just unclear as to how it would..
^ Ahh good im getting tired of arguing 
lol
Anyways here's a useful post:
No point in removing the headers or exhaust, your right, it wouldn't have anything to do with it. If the cars not shifting at WOT from 4th to 5th, sounds like something electrical. I had a problem kindaaa like that in my Prelude, would not shift from 3rd to 4th unless it was done very slowly. Turned out it was a dying Transmission Control Unit (TCU) don't know if the IS has one of these though, or if its integrated somewhere else.
lol Anyways here's a useful post:
No point in removing the headers or exhaust, your right, it wouldn't have anything to do with it. If the cars not shifting at WOT from 4th to 5th, sounds like something electrical. I had a problem kindaaa like that in my Prelude, would not shift from 3rd to 4th unless it was done very slowly. Turned out it was a dying Transmission Control Unit (TCU) don't know if the IS has one of these though, or if its integrated somewhere else.
JB - I tested this in a safe area/no cars around...my car upshifted to 5th no problem. Again, I had the valve recall done, but declined the gas pedal 'fix' when they suggested it at the same time. Hope this helps
I'm willing to try this to help you out, but when I get pulled over, do you mind if I give them your badge number? I am trying to help you out after all. haha I wish. If I have a safe opp. I will give it a go and report back.
This does NOT have to start from a dig right? 75mph? 85?
This does NOT have to start from a dig right? 75mph? 85?
^ Ahh good im getting tired of arguing lol
Anyways here's a useful post:
No point in removing the headers or exhaust, your right, it wouldn't have anything to do with it. If the cars not shifting at WOT from 4th to 5th, sounds like something electrical. I had a problem kindaaa like that in my Prelude, would not shift from 3rd to 4th unless it was done very slowly. Turned out it was a dying Transmission Control Unit (TCU) don't know if the IS has one of these though, or if its integrated somewhere else.
lol Anyways here's a useful post:
No point in removing the headers or exhaust, your right, it wouldn't have anything to do with it. If the cars not shifting at WOT from 4th to 5th, sounds like something electrical. I had a problem kindaaa like that in my Prelude, would not shift from 3rd to 4th unless it was done very slowly. Turned out it was a dying Transmission Control Unit (TCU) don't know if the IS has one of these though, or if its integrated somewhere else.
I'm willing to try this to help you out, but when I get pulled over, do you mind if I give them your badge number? I am trying to help you out after all. haha I wish. If I have a safe opp. I will give it a go and report back.
This does NOT have to start from a dig right? 75mph? 85?
This does NOT have to start from a dig right? 75mph? 85?
. Correct, this is just in general, not specific to starting from a stop or rolling on the highway.
UPDATE:
Went to the dealership today and talked with the service manager. The main issue they are having right now is that no one else has reported the same issue, and rarely do people actually go that fast, which is totally understandable. Basically I need to find someone locally that has an IS350 that has had the recall done and see if that person runs into the same problem upshifting. If they do, then we know it is because of the recall and he can start a paper trail with the issue and complaint. If they don't, then that would mean it's my car specifically, which he thinks would be better because then he can more easily justify replacing my entire ECM and see if that fixes the issue.
I guess now I just need to find a local IS350, or someone who has video of them doing WOT from 4th to 5th with no issue after having the recall done. I would also need the VIN so he can look it up and verify the car has had it done.
Soooooooooooooooo frustrating.. I just want my car to work like it did BEFORE the stupid recall!
Went to the dealership today and talked with the service manager. The main issue they are having right now is that no one else has reported the same issue, and rarely do people actually go that fast, which is totally understandable. Basically I need to find someone locally that has an IS350 that has had the recall done and see if that person runs into the same problem upshifting. If they do, then we know it is because of the recall and he can start a paper trail with the issue and complaint. If they don't, then that would mean it's my car specifically, which he thinks would be better because then he can more easily justify replacing my entire ECM and see if that fixes the issue.
I guess now I just need to find a local IS350, or someone who has video of them doing WOT from 4th to 5th with no issue after having the recall done. I would also need the VIN so he can look it up and verify the car has had it done.
Soooooooooooooooo frustrating.. I just want my car to work like it did BEFORE the stupid recall!
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Well, I have no idea what has changed in the past 2 weeks, I haven't driven the car much at all cause I have a work car, but today on my way to the dealership to get my oil changed I decided to go WOT and see if it would do it again.
IT UPSHIFTED! No idea what the issue was but got it up to 120 real quick without ever having to let off the gas. Went right into 5th with no hesitation. I wish we could have diagnosed the issue when it was happening to figure out why it was happening, but it works now and I guess that is all that matters.
Thanks to everyone who tried to help me out with this issue. Hopefully it doesn't happen again!
IT UPSHIFTED! No idea what the issue was but got it up to 120 real quick without ever having to let off the gas. Went right into 5th with no hesitation. I wish we could have diagnosed the issue when it was happening to figure out why it was happening, but it works now and I guess that is all that matters.
Thanks to everyone who tried to help me out with this issue. Hopefully it doesn't happen again!
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