Important Preliminary Checks
Checks 
 | Action 
 | 
Before Using This Section 
 | Before using this section, you
should have performed the Powertrain On-Board Diagnostic  System Check. Several
  of the  following symptom    procedures call for a careful  visual and physical
  check.  The visual and   physical  checks are very important.  These checks
  can lead to  correcting   a problem  which may save  valuable time. 
 | 
Visual
and Physical Checks 
 | 
|     •  | Check the VCM grounds for being clean, tight and in their proper
location. Refer to Vehicle Control Module Description
. |  
  
|     •  | Check the vacuum hoses for splits, kinks and proper connections,
as shown on the Vehicle Emission Control Information label. |  
  
|     •  | Check thoroughly for any type of leak or restriction. |  
  
|     •  | Check for air leaks at all the mounting areas of the intake manifold
sealing surfaces. |  
  
|     •  | Check the ignition wires for the following conditions: |  
  
|     •  | Check the wiring for the following items: |  
  
|     •  | The following symptom tables contain groups of possible causes
for each symptom and cover several engines. The following symptom tables cover
        several engines. The order of these procedures is not important. If
  the     scan   tool readings do not indicate the problems, then proceed
in   a logical     order,   easiest to check or most likely to cause first.
In   order to determine     if  a  specific vehicle is using a particular
system   or component, refer    to  
Engine Controls Schematics 
  for an application. |  
  
 | 
Symptom 
 | 
- Verify the customer complaint.
 
- Locate the correct symptom table.
 
- Check the items indicated under that symptom.
 
 
Use the following tables when diagnosing a symptom complaint. 
 |