User Manual

Retrieving Codes

ADDITIONAL TESTS FOR EEC-IV SYSTEMS

43 Chapter 4

■ The Cylinder Balance Test can be repeated by

pressing and releasing accelerator pedal (as described

in step 6, on page 41) within two minutes after the

last cylinder balance code is retrieved.

Use the A, B, C, and D examples in the "TEST

RESULTS CHART" to determine the meaning of the

test results. The chart uses the #2 cylinder as an

example, but the procedures are the same for any

cylinder.

TEST RESULTS CHART

Test Results Chart (Examples) Explanation

A: If a code 90 is retrieved the 1st time the cylinder balance

test is performed (example A in TEST RESULTS

CHART), the system is OK, and no further testing is

required. Proceed to step 8.

TEST RESULTS

TEST PROBLEM POSSIBLE

1st 2 nd 3rd

DEFINITION INDICATION CAUSE

A 90 * * System passed System passed. •System OK

1st test All cylinders are

contributing

equally.

B 20 90 * Fails 1st test Weak cylinder, •Bad spark plug

Passes 2nd test cylinder is firing, wire or spark plug

but not contribu- •Partially clogged

ting the same as injector or injector

the others circuit problem

•Mechanical

problem - rings,

valves, etc.

C 20 20 90 Fails 1st test Same as above, but • Same as above,

Fails 2nd test condition is more but the condition

Passes 3rd test severe. is more severe.

D 20 20 20 Fails 1st test Very weak or dead •Bad spark plug

Fails 2nd test cylinder wire or spark plug

Fails 3rd test •Open or shorts on

injector circuit,

clogged injector

•Mechanical

problem - rings

valves, etc.