I'm working on an old 1981 368 / 6.0 Cadillac Deville with the V8 / 6 / 4 with cylinder switching. It has had some trouble and doesn't run correctly. In this video, I am running through the built in diagnostic routines that can be accessed in the air conditioning controls. It starts with a readout of trouble codes, then moves into various tests. You can test all of the critical switches, such as brake lights, cruise control, and transmission selector. Then there are about a dozen engine parameters that can be viewed, such as throttle position, oxygen sensor, temperature sensors and so forth. Then, there is a set of tests for the actuators and cylinder selection that can be run. I have a trouble code 30 currently that is an issue with the idle speed control system. I am running the tests following the GM shop manual and later will be diagnosing the code 30.
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