Engine Controls - Basic Testing: Introduction
NOTE:
Monaco and Premier models are manufactured with either an early or late design. Only late design models are covered in this article. Late design models are equipped with DIS, with engine controller (SBEC) located next to battery. Service procedures for early design models, with engine code Z7X711, are the same as those found in the equivalent articles for the 1990 models.
The following diagnostic steps will help prevent overlooking a simple problem. This is also where to begin diagnosis for a no-start condition.
The first step in diagnosing any driveability problem is verifying the customer's complaint with a test drive under the conditions the problem reportedly occurred.
Before entering self-diagnostics (if equipped), perform a careful and complete visual inspection. Most engine control problems result from mechanical breakdowns, poor electrical connections or damaged/misrouted vacuum hoses. Before condemning the computerized system, perform each test listed in this article.