'92 Saturn locks chattering

Check for faulty relays/module. A bad connector or wiring !

DESCRIPTION & OPERATION
The power door lock system uses electric switches to lock and unlock all of the vehicle doors simultaneously from either of 3 switches. Two of the switches are on the inside of the front doors. The third switch is contained within the key cylinder assembly, and actuated with a key. The system consists of 3 switches, a door lock module containing 2 relays, and a door lock actuator in each door. See Fig. 1.
Available also, is an electric liftgate release system on wagon models. This system consists of a liftgate release actuator, switch and relay. Further information on this system is not available from the manufacturer.
When a door lock switch is moved to the lock position, current flows through 30-amp fuse located in the underhood junction block, through 20-amp fuse located in the instrument panel junction block, through the coil of a lock relay, and through the door lock switch to ground. This energizes a lock relay and closes the relay switch contacts, which supplies ground paths for the door lock motors. This locks all doors.
When a door lock switch is moved to the unlock position, current flows through 30-amp fuse located in the underhood junction block, through 20-amp fuse located in the instrument panel junction block, through the coil of the unlock relay, closing the relay switch contacts which supplies ground paths for the door lock motors, allowing the door locks to unlock.
When any 2 switches are depressed simultaneously to different positions, the zero volt differential across the door lock actuators perform the operation indicated by the remaining depressed switch. When any 2 switches are depressed simultaneously to the same position, the appropriate door lock/unlock operation is performed.

My take on the this is when you have the lock's going crazy again look at the drivers door lock cylinder make sure the key hole opening is facing straight up and not turned to the left or right. On the other side of the cylinder is a door lock switch and when that cylinder stay's to left or right the power lock's will stay on constantly. See if it is when the lock's are going crazy and let me know and we will go from there. That is the most common reason I have seen for that happening. If you want we can look into that code 26 also.

No if you replace the computer you won't fix that code you will be wasting your money.A code 26 say's you have a fault in the quad circuit doesn't mean within the computer itself. Just to give you an idea of what the quad circuit includes some of it is the radiator cooling fan, canister purge, speedometer, power seat belt, egr, your check engine light. If any of those fail's it will set that code 26. So if I see a code 26 with a code 32 I would be looking at that egr solenoid on the valve cover.I would also get a hand vacuum pump and check to make sure the egr valve hold's vacuum and doesn't stick. Make sure the egr port isn't clogged. Also inspect the vacuum line's going to egr solenoid and egr valve. Do you have a multimeter so we can check that solenoid?

I can't see how the egr solenoid affected your gas mileage. So your egr valve hold's vacuum and doesn't stick?As far as just getting a code 26 I would say most likely you have a bad canister purge solenoid but you would have to test it when it was hot and the code was active.

You get a hand vacuum pump and check to make sure the egr valve hold's vacuum and doesn't stick. You hook the hose of the hand vacuum up to the vacuum nipple of the egr valve and pump it up to about 20 inch pound's of vacuum see if it hold's the vacuum if it does then release the vacuum see if the valve stick's open. If it hold's vacuum and doesn't stick the egr valve is good.I posted a diagram of where the canister purge solenoid is. When the engine is hot and the code 26 is active you would unplug the connector to the canister purge solenoid and test the solenoid's resistance value with a ohm's meter it should read 22-42 ohm's most of the one's I have tested test as a open meaning no resistance value which is bad. Sometimes there hard to catch testing bad depends on how bad it is.

That just mean's it will make a lot easier to find the problem. Does the radiator cooling fan work?If it doesn't check the 30amp green maxi fuse to see if it's blown. That will set a code 26 right off the bat as well. Also ohm's check the canister purge solenoid like I told you how to do. So how did the egr vacuum test come out?If you haven't done that yet I think they rent the hand pump's at auto zone auto part's.