To fix the speedometer on a 1991 Oldsmobile 88, first check the speedometer cable for any breaks or disconnections, as a damaged cable is a common issue. If the cable is intact, inspect the speedometer itself for any signs of malfunction or wear. You may also need to check the vehicle's vehicle speed sensor (VSS) if equipped, as a faulty sensor can affect the speedometer's accuracy. If these components are functioning properly, consider consulting a professional mechanic for further diagnosis or replacement of the speedometer unit.
check your fuses
I'd suggest you take the car to a speedometer repair specialist. They can remove, repair and calibrate the spedometer.
Good luck, I've got the same issue
1986 - 1991.
should be under the hood.
A motor from a 1991 Oldsmobile will fit into a 1996 Oldsmobile Delta 88. The motor mounts will need to be changed.
It should take P205/75R/15. If that's not the size that's on it then call a local tire dealer to be sure. My wife has a 90 Olds 88 and they should be the same.
If the car is fuel injected (not sure for 1991) then the fuel pump is in the gas tank.
U need a new speedometer cable. It runs from the transmission to the speedometer. They tend to break in half or just seize up after they get so old. They are easy to replace, it takes to people to do it but it is really easy to do. I hope I helped you.
Have vehicle scanned to determine the problem usually in the emission control system
To fix the speedometer on a 1988 Caprice Classic, first check the speedometer cable for any breaks or disconnections. If the cable appears intact, inspect the speedometer gear in the transmission for wear or damage, as this can affect accuracy. Additionally, ensure that the instrument cluster connections are secure and free from corrosion. If all else fails, consider replacing the speedometer or seeking professional help to diagnose any underlying electrical issues.
How many olds delmont 88 where made in 1968