This bulletin has been revised to clarify Step 9. Revision to Chart A-3 (page 2 of 3) - Step 9 of P.S.B. 87-630-107 and 87-638-111, Page 11. The revision in Step 9 is required to make the chart work properly. If the crank sensor is indexed so that a window is in front of the hall switch, the crank signal will be pulled low and the injector test light will not flash.
These revisions are presented to clarify the diagnostic procedure for the C"3"I ignition system. These charts supercede the A-3 charts and C-4 charts in the 1986 and 1987 service manuals for the engines listed above.
This revision is presented to clarify Chart C-4 for 1986-87 A, C, and H carlines equipped with 3.8L (VIN 3 and B) engines. This revision replaces the appropriate page in the service bulletin. Step 4 has been revised to include Type II ignition system check.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.