4L60e will not upshift at WOT
yeah that's just it, i didn't change gears and my speedometer all of a sudden became 15mph which in turn has caused the no wot upshifts. Something in the wiring to the PCM or VSS could be the culprit, when I have time I taking it to an electrical shop to check a couple of things.
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
P0121 code only affects 98 cars that are cammed. The transmission shifts from 1st to 3rd or even 4th. I have had two 98 cars which do the same, the solution was disabling P0121.
i haven't really checked the speedo. i hope its the tune. but the fact is that the tune was good then all of sudden the tune is not like your issue. i replaced the trans but still have the same issue at WOT. at least with this trans it shifts fine at each gears when driving normal but at WOT it doesnt shift from 2-3. it'll shift from 1-2 fine. Once the car gets to TX i'll take it to LG to tune it.
I just took the car to a tuner..the problem of course like I knew was not in the tune...technically. He adjusted the table so the car thinks it has a higher gear which corrected the speedometer...however my tach is still off about 1000rpm. When I'm seeing 7000rpm it's actually closer to 6 so I'd let my foot off to not blow the motor and hence the car wouldn't shift. He lowered the shift points a little and yes the car shifts at WOT although my tach is redlined at 7krpm. Basically he put a band aid on it and my tach is still off and shift points aren't optimal for performance. The reason why the tach and speedo are off in the first place? That nobody knows for sure and I may start by replacing the cluster....
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Verdad Gallardo I believe so...the tach being off is my problem, it might have shifted before at wot without lowering the shift points I just let my foot off right before 7k rpm so I wouldn't blow the motor.
Actually that can't be right, the computer wasn't commanding the wot shift, I guess the wot shift is occuring because the combination of correct speedo, lowered shift points and the fact I'm leaving my foot on right up to the redline now ?
Update my problem all along was my gauge cluster. I just bought a used cluster off here and it's shifting right around 6k now. Off course my speedo is off again now the other way...speedo says 40 and actual speed is 47. Shift points are also lower then I want them so I have to get those adjusted. What I don't get is why were scanners saying the computer wasn't commanding the shift when it probably was shifting i was just letting my foot off near 7k on the tach and what could have caused my tach to be 1000rpm off and my speedo to be off 15 mph all of a sudden??
Also with the new cluster I'm getting a TCS off light(my car has no traction control) and an aps inop light are these 2 lights able to be tuned out through the PCM?
Also with the new cluster I'm getting a TCS off light(my car has no traction control) and an aps inop light are these 2 lights able to be tuned out through the PCM?
