Up Shift Indicator
Thread Starter
2nd Gear
Joined: Apr 2004
Posts: 2
Likes: 0
From: La Plata MO
Up Shift Indicator
I have a 1988 with a 4 speed automatic. The up shift indicator on the dash has recently been coming on while in overdrive. If I let up on the gas pedal or go up a hill, the light will temporarily go off. The engine is reving at about 1700 to 1800 rpm while doing 60 mph, about 100 to 200 rpm faster than usual. This seems to happen more often in the afternoon than in the morning. I'm assuming it's temperature related, because it's warmer then. Has anyone else had this problem and if so, what's going on?
Intermediate
Joined: Dec 2003
Posts: 27
Likes: 0
From: Kaysville Utah
Re: Up Shift Indicator (lilblackvette)
I believe the up shift indicator is just basically a vacuum sensor. It'll come on at medium throttle but if you let off the gas or stomp on it, it'll go off becuase it isn't in the vacuum range any more.
Drifting
Joined: Oct 1999
Posts: 1,722
Likes: 0
From: Gloucester Va
Re: Up Shift Indicator (89Alice)
You know that shift litght thing has always puzzled me. My 88 it came on once or twice through out the time I had it stock. Funny thing is I got the car and the torque converter was not locking up and I never knew it because I didn't know it was suppose to, or what that even wasa at the time.
THe extra RPMS are because your TCC (torque converter clutch) is most likely not locking up in 4th giving you that sweep 1500RPM at 55-60MPH. I found the problem to be in the brake switch. Replace it and see what happens. Don't check the brake switch with a volt meter. I did this and it checked out fine. But that converter wouldn't lock up with it in the car. Once replaced I've not had a problem since. They are a little bit of a pain to put in but they are cheap as well so it off sets the pain. :thumbs:
THe extra RPMS are because your TCC (torque converter clutch) is most likely not locking up in 4th giving you that sweep 1500RPM at 55-60MPH. I found the problem to be in the brake switch. Replace it and see what happens. Don't check the brake switch with a volt meter. I did this and it checked out fine. But that converter wouldn't lock up with it in the car. Once replaced I've not had a problem since. They are a little bit of a pain to put in but they are cheap as well so it off sets the pain. :thumbs:
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Re: Up Shift Indicator (Wheelman)
The owners manual for my 91 says:
"This light will come on approximatley one minute after you reach crusing speed to remind you when to shift into 6 (Sixth) gear for a manual and D (Automatic Overdrive) for an automatic transmission."
I see it when I'm hitting ~51 MPH in drive. If I back off to ~45, it goes out.
[Modified by Steel Blue 91, 7:55 AM 5/2/2004]
"This light will come on approximatley one minute after you reach crusing speed to remind you when to shift into 6 (Sixth) gear for a manual and D (Automatic Overdrive) for an automatic transmission."
I see it when I'm hitting ~51 MPH in drive. If I back off to ~45, it goes out.
[Modified by Steel Blue 91, 7:55 AM 5/2/2004]
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