I have 3 door knobs on outside doors that are loose and need to be tightened. the knobs have come completely off sometimes when we go out the doors. how do I tighten the knobs so they are not loose?

No make, no model, no year equals no help.

What door knob are we talking about,, a door knob has screws on the back side, usually a #2 phillips head screwdriver will work in the screws.. If you are talking about a different knob.. please repiy on here... please mark as helpful..

You need a special puller for the inside door panel. Have to go to an autoparts store for it. Then you take out all the screws on the door panel. The you use the puller on the bottom and sometimes the sides to LOCATE and REMOVE the fasteners..Lift the panel up and away from the door. Careful about any wires that might be connected to switches. Unplug those if present. You will now be looking at a sheet of sound deadening material that has a tar like substance on it. You cannot really save this and it is messy. remove it and then you can see the internal door and window parts. Be careful because the parts are sharp. Long sleeves and gloves are recommended. See if you can reach in under the window and feel for the bolts. If you cannot then the window has to be removed. Locate and remove the glass retainer and remove the window. Then remove any bolts holding the window mechanical parts. Then you should be able to get to the bolts for the mirror.

use match sticks to fix it

Remove the knob by pushing in the small pin on the edge of the knob shaft. Then use a screwdriver in the small inset on the edge of the handle cover to pop the cover off. Tighten the 2 screws under the cover, replace parts.

If its the windshield mirror, gm usually uses a phillips or torx head screw to tighten the mirror to the base, which is glued to the glass with a special adhesive. If the screw is tight and it's the mirror joints that are loose, replace the mirror. If it's the door mirror, the inner trim on the door needs to be removed to tighten the mounting bolts. If the outside foldaway joint is loose, you will probably need to replace the complete mirror.

If it is not the OLD style door knob, tighten the two screws next to the knob. If that does not fix it it will probably need repleced.

Toyota Corolla 1988-1997 Repair Guide Door Locks - REMOVAL & INSTALLATION
(see Figure 1)

1. Disconnect the negative battery cable.
2. Remove the door panel and watershield. Remove the service hole cover.
3. Disconnect the door outside opening linkage. Remove the two mounting bolts and remove the door handle if in need of replacement.

Fig. 1: Power door lock control system component locations

1. Disconnect the lock cylinder control linkage.
2. Remove the lock knob and the child protector lock lever knob.
3. Remove the lock assembly retaining screws and remove the door lock. If equipped with power locks, disconnect the electrical harness.
4. To remove the lock cylinder, remove the lock cylinder retaining clip and pull the cylinder from the door.

To install:

1. Coat all the door lock sliding surfaces with multi-purpose grease.
2. Install the outside handle with the two retaining bolts, if removed.
3. Install the door lock solenoid linkage to the door lock.
4. Connect the link to the outside handle.
5. Install the lock knob and the child protector lock lever knob.
6. Install the door opening control link tighten the mounting bolts to 48 inch lbs. (5 Nm).
7. Install the door lock cylinder control linkage.
8. Install the door panel and watershield.
9. Reconnect the negative battery cable.

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When you first tightened the screws, the mechanism may have been loose enough to allow the actuator bar the connects the inside knob to the outside lever to work loose. When you tightened it you may have jambed that tight so things didn't work. When you disassembled everything, you may have lost that part. The springs are usually integrated into the catch part and are not removeable. Sometimes it helps to take everything completely off the door including the catch that goes in the edge of the door. Then reassemble it on a table to see what works and what doesn't. If that doesn't help, take all the pieces into Lowes at the key desk and they will be glad to help you.

A couple of ideas: Sometimes the top of the knob is a cap which can be levered off with a sharp blade. Or, there is a grub screw (which may need a hex key to turn it) in a hole on the underside of the knob.