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Engine - #6 Cylinder Misfire (Vacuum Leak)

87cadillac8

Bulletin No. T-88-49
File in Group 6E
Number 55
Corp. Ref. No. 816503
Date Nov. '87
SUBJECT: ENGINE MISS AT THE #6 CYLINDER

MODELS AFFECTED: 1986-1988 BROUGHAMS

FIGURE 1 - VACUUM CIRCUIT:




Some 1986-1988 Broughams may experience a condition of an engine miss at the #6 cylinder. This condition may be caused by a vacuum leak in the vacuum circuit between the vacuum fitting in the #6 intake manifold runner and the hoses and tees connected to that fitting (see Figure 1).

To repair this condition, the following items should be examined:

^ Check for split vacuum hose between the vacuum fitting and HVAC vacuum tank (refer to Figure 1).
^ Check HVAC vacuum tank for cracks or open seams.

^ Check for loose/disconnected vacuum hoses/fittings.

^ Check remainder of hoses for splits.

If the above repair does not correct the misfire condition, refer to the appropriate model year Cadillac Service Information Manual, Section 6E1 "Symptoms".