Hard Start/Long Crank/Erratic Start/Erratic Crank - Mazda B-Series 1997 Workshop Manual

TROUBLESHOOTING GUIDE
FT
Is a strong blue spark visible at each disconnected
high-tension lead while cranking engine?
e
3
HARD STARTILONG CRANKIERRATIC STARTIERRATIC CRANK
- -
Fuel line pressure:
240-280
kPa I2.5--2.8 kgflcm2, 35--40 psi)
3
Yes
1
GO to next step
DESCRIPTION
Perform Fuel Line Pressure Inspection.
ua= page FT-147
Is fuel line pressure correct?
Check camshaft position sensor :signal at PCM
=
page FT-168,174,180
If OK, check as follows:
Crankshaft position sensor
Section G
High-tension leads Section G
Spark plugs Section G
If not OK, check wirina harness
Starter cranks engine at normal speed but engine requires excessive cranking time
before start
Battery in normal condition
70
to next step
- -
No
/
Zero or low:
1
Check fuel pump circuit
page FT-151
ACTION
Diagnostic trouble code displayed
Check for cause (Refer to Diagnostic Trouble Code
chart)
a s
page FT-77
No diagnostic trouble codes displayed
Go to next step
STEP
1
4
1
Perform Fuel Line Pressure Hold Inspection.
i
page FT-147
Yes
INSPECTION
Check pressure regulator diaphragm
D ~ P
page FT-154
High:
Check pressure regulator for high
pressure cause
e page FT-154
Check for clogged fuel return li~ie
--
Go to next step
Are any diagnostic trouble codes displayed
during Key On Engine Off, Key On
Engine Running or Continuous Memory inspection?
as page FT-71
1
/
Does fuel line pressure hold?
I
Yes
No
Disconnect the vacuum hose from the pressure
regulator and plug hose. Start the engine.
Does the fuel line pressure remain within
f20 kPa i0.21 kgf/cm2, 3 psi) while driving vehicle
Yes
Check pressure regulator diaphragm condition
w page FT-154
If condition is OK, check injector
page FT-155
If
condition is not OK, replace pressure regulator
Go to next step
Check for clogged fuel filter
l 6 I
Connect the vacuum hose to the pressure
1
Yes
Go to next step
regulator. Install a vacuum gauge to the intake
I / I
no change, replace pressure regulator
- -
manifold. Start the engine.
Does fuel pressure gauge reading increase as the
1
vacuum gauge reading decreases and/or does 1
fuel pressure gauge reading decrease as the
i
vacuum gauge reading increases?
i
pump pressure regulator
Start the engine
Check that fuel pressure reading changes as
vacuum changes
If chancles, check vacuum line