check engine light stays on. fixed myself & repair shop too but problem continues. suggestiions?

If you can describe what code caused the check engine light to stay on, would be easier to zero in on the source of the problem. It depends if what was repaired was what really caused the problem to begin with. Suggested sources would be www.alldatadiy.com or Mitchell Online, which not only mentions possible codes for a vehicle, but also a flow chart to find the problem. If you go one of those roots, it is important not to skip steps to avoid misdiagnosing and/or unnecessary parts replacement. Sometimes the problem could be as easy as fixing a broken wire circuit. Hopefullly that could get you going in the right direction.

Assuming you have the On Board Diagnostic system (OBD), the problem will be much easier to diagnose. All vehicles produced prior 1996 were equipped with OBD1. There should be a large plastic plug in easily accessible under your dash near the steering column. You can read the codes with a simple paper clip. The plug in has quite a few cells used for plugging a scan tool in, but you only need to put both ends of the paper clip into the top right two cells. Turn your ignition to "Run" (Engine is still off) before putting the paper clip in the plug in. The 'Check Engine Light' will begin to flash. It should repeat each code three times. For example, 12 would be read like so. The light would flash once, then after a very short pause, flash twice. That would mean Code 12. After it runs through all the codes, it should repeat the process as long as the paper clip is plugged into the plugin.

Sorry, I forgot to mention. It is highly recommended you find a shop manual specific to your Oldsmobile. Purchase one off of eBay. Don't buy a 1986 Oldsmobile Cutlass Supreme Service Manual if you have a 1985. There are differences, even if the vehicle looks exactly the same as one the year after it. Buying a GM Service Manual will help you far more than any Haynes or Chilton Manual you can find at AutoZone.