4L60E Not Downshifting.....
4L60E Not Downshifting..... Car is having some issue's with the trans, started having problems last sunday.....
Went to the track last sunday, went to make my 1st pass, blew the tires off, let out, went WOT again only to have it stuck in O/D and not want to go anywhere!
On the way home I went WOT again from a 50ish roll and it didn't even down shift, just stayed in overdrive, felt like I was using the acel. button on the cruise control!
She will however downshift if you manually do so, seems like once she goes in to O/D she doesn't come out until you slow to a stop!
Anybody else ever had this issue and figure out what the problem was?
Went to the track last sunday, went to make my 1st pass, blew the tires off, let out, went WOT again only to have it stuck in O/D and not want to go anywhere!
On the way home I went WOT again from a 50ish roll and it didn't even down shift, just stayed in overdrive, felt like I was using the acel. button on the cruise control!
She will however downshift if you manually do so, seems like once she goes in to O/D she doesn't come out until you slow to a stop!
Anybody else ever had this issue and figure out what the problem was?
Before I start, let me say that I'm not a pro. When I buy one of those new camera's, I ask for the GoAmateur option.
No codes?
Are you sure the torque converter is unlocking when you manually shift it down to a lower gear? I'm just shooting in the dark, but if you're stuck in 4th, and the converter is locking up like is should you maybe the lockup solenoid is stuck in the "on" position keeping anything from happening.
No codes?
Are you sure the torque converter is unlocking when you manually shift it down to a lower gear? I'm just shooting in the dark, but if you're stuck in 4th, and the converter is locking up like is should you maybe the lockup solenoid is stuck in the "on" position keeping anything from happening.
Nope, no codes!
Couldn't tell ya for sure if she's unlocking while manually downshifting, sounds like you're theory make's sense and also thought it was a noid problem myself!
Figured somebody else would have this problem and chime in on what it was!
Couldn't tell ya for sure if she's unlocking while manually downshifting, sounds like you're theory make's sense and also thought it was a noid problem myself!
Figured somebody else would have this problem and chime in on what it was!
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
I read your question minutes after you first posted it, but I don't have the answer and don't recall anyone else here reporting that in the past year.
The shifting is completely controlled by the PCM, the trans makes no decisions. Of course, if a shift solenoid is bad the trans does not follow the PCM's "instructions".
A bad VSS or TPS (or MAP or MAF?) sensor might confuse the PCM and cause it to delay downshifting until very low speeds are reached; e.g. ignoring the throttle position. Such problem usually but not always result in a code.
Does the trans downshift correctly with the shifter in [D3]?
What kind of scanner did you use to check for codes?
I assume the speedometer works?
Do you have access to a scanner that can monitor the TPS, MAP and MAF?
The shifting is completely controlled by the PCM, the trans makes no decisions. Of course, if a shift solenoid is bad the trans does not follow the PCM's "instructions".
A bad VSS or TPS (or MAP or MAF?) sensor might confuse the PCM and cause it to delay downshifting until very low speeds are reached; e.g. ignoring the throttle position. Such problem usually but not always result in a code.
Does the trans downshift correctly with the shifter in [D3]?
What kind of scanner did you use to check for codes?
I assume the speedometer works?
Do you have access to a scanner that can monitor the TPS, MAP and MAF?
Thanks for the reply!
Yes, the trans will downshift once WOT in d3!
As far as the code reader is all I have to check with, cheap autozone one I have had for years lol!
Speedo works as it should, and yes I do have a good friend of mine that could moniter those things with HPtuner's (I would assume would work?)
Yes, the trans will downshift once WOT in d3!
As far as the code reader is all I have to check with, cheap autozone one I have had for years lol!
Speedo works as it should, and yes I do have a good friend of mine that could moniter those things with HPtuner's (I would assume would work?)
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
Thanks for the reply!
Yes, the trans will downshift once WOT in d3!
As far as the code reader is all I have to check with, cheap autozone one I have had for years lol!
Speedo works as it should, and yes I do have a good friend of mine that could moniter those things with HPtuner's (I would assume would work?)
Yes, the trans will downshift once WOT in d3!
As far as the code reader is all I have to check with, cheap autozone one I have had for years lol!
Speedo works as it should, and yes I do have a good friend of mine that could moniter those things with HPtuner's (I would assume would work?)
So, in [D3], when you go WOT, it will downshift into 2nd, but in [OD] it will not downshift until you reach very low speeds. Very strange indeed.
In respect to white2001formula's comments, a stuck TCC valve would not prevent the trans from downshifting. But just to be sure, can you feel the TCC engage and disenage when in [OD]?
So,
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Registered User
Joined: Jul 2014
Posts: 1
Likes: 0
won't downshift I have the same problem with my 98 TA. Had the scan tool on it it will shift to 4th won't downshift on WOT. Until it get to slow speeds. I changed the TPS with no fix. Just had trans rebuilt 3 weeks ago.
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