87 Senator Problem

[Raeven_Zero]

My automatic transmission on my 87 Senator 3.0i sometimes randomly kicks down into 1st gear and a dummy light comes on like you would see in a manually shifted car. I have to quickly toggle the key off and then back on to reset the fault. The tranmission otherwise runs fine and has the right amount of fluid along with a brand new filter.

[Jeff Pozorski]

It sounds like your car's computer is sensing a problem with the tranny and going into "cripple mode". This is meant to warn you of a problem and to allow you to drive it to a dealer for service before the tranny goes out for good. Take it to your nearest dealer and they can diagnose what is wrong, or going wrong, with your tranny.
Good luck.

[GTJIM]

There is a kickdown switch under the accelerator pedal which is manually operated - by foot! - when the pedal is shoved tothe metal. This sometimes jams engaged causing all sorts of fun and problems. You can see it by lifting the driver's foot well carpet. Sometimes the switch has just jumped out of its retainer and needs refitting.
If there is no switch there you have an earlier type of trans that has a kickdown cable (or "TV" cable) which needs to be correctly adjusted for the trans to work correctly. This cable is hooked into the accelerator linkages.
The error codes are recorded by the ECU and any Opel Dealer should know how to read them and tell which error has occured.

HTH