Daewoo NUBIRA User Manual

1F – 376IENGINE CONTROLS
DAEWOO V–121 BL4
BACKFIRE
Fuel ignites in the intake manifold, or in the exhaust
system, making a loud popping noise.
Important : Before diagnosing the symptom, check ser-
vice bulletins for updates.
Step Action Value(s) Yes No
1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-
tant Preliminary
Checks”
2
1. Inspect for crossed or crossfiring ignition wires.
2. Check the ignition system output voltage for all
cylinders using a spark tester.
3. Inspect the spark plugs for excessive wear,
burned electrodes, improper gap, or heavy de-
posits..
Is the problem found?
Go toStep 3 Go toStep 4
3 Repair or replace any ignition system components
as needed.
Is the repair complete?
System OK
4
1. Check the fuel system operation.
2. Check the fuel injectors by performing an injec-
tor diagnosis.
Is the problem found?
Go toStep 5 Go toStep 6
5 Repair or replace any fuel system components as
needed.
Is the repair complete?
System OK
6
1. Inspect the Exhaust Gas Recirculation (EGR)
gasket for a leak or a loose fit.
2. Check the EGR valve for proper operation.
3. Inspect the intake manifold and the exhaust
manifold for a casting flash.
Is the problem found?
Go toStep 7 Go toStep 8
7 Repair or replace any components as needed.
Is the repair complete?
System OK
8
1. Inspect the timing belt for proper installation
and tension.
2. Check the engine compression.
3. Inspect the intake manifold gasket and the ex-
haust manifold gasket for leaks.
4. Check for sticking or leaking valves.
5. Repair or replace any components as needed.
Are all checks and corrections complete?
System OK

Daewoo NUBIRA Specifications

General

Brand	Daewoo
Model	NUBIRA
Category	Automobile
Language	English