1995 Buick Roadmaster Estate Wagon. Has Corvette LT-1 350 V-8. 60,000 miles
Sometimes when starting the engine cold the check engine light comes on and the radiator cooling fan runs for a few minutes. After the fan stops, the light goes out. After several days or even weeks, it does it again. Engine operation is normal, with normal temperatures on the dash temp gauge and no sign of overheating or anything else wrong. This has been going on for several months. Car passed a California smog check a few weeks ago with no problems. Luckily, the light stayed off during the test. I tried to pull codes by inserting the code key under the dash, but this car is an interim model made in the waning days of OBD1 and before OBD2 took over, so the code key won't work. Any suggestions?