Low Idle/Stalls During Deceleration - Mazda B-Series 1997 Workshop Manual

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Is fuel lrne pressure correct?
page FT-l
1
N ;
7
low:
Check pressure regulator diaphragm
I
Fuel line pressure:
1
240-280 kPa (2.5-2.6 kgf/cm2, 35-40 psi)
Check fuel pump circult
a*
page FT-151
FT
TROUBLESHOOTlNG GUIDE
1
1
High:
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Check pressure regulator for hlgh pressure cause
w
page FT-154
Check for cloaaed fuel return line
9
1
LOW IDLEISTALLS DURING DECELERATION
6
,
Disconnect inertia fuel shutoff switch connector.
Crank engine for 5 seconds. Does pressure drop
more than 34 kPa (0.35 kgf/cm2, 5 psi} by the end
,
of 5 second crank cycle?
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5
f --
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7 Check the throttle body for the following:
1
Damage
Sticking, bindlng or grabbing condition
Vacuum leaks
Proper attachment to accelerator cable
Is the throttle body OK?
DESCRIPTION
Engrne stops unexpectedly at beglnnlng of deceleration or recovery from deceleration
Vlsually look for fuel leakage at Injector 0-r~ng,
pressure regulator, and fuel Ilne. Service as
necessary.
Perform Fuel Pressure Hold Inspectlon.
page FT-154
page FT-150
If condrtlon
IS
OK, check Injector
Does fuel llne pressure hold?
. g
page FT-155
If condltlon
IS
not OK, replace pressure regulator
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ACTION
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Go to step 3
Go to next step
- p p
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p p
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Diagnostic trouble code displayed
Check for cause (refer to Dlagnostlc Trouble Code
chart)
=
page FT-77
STEP-
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INSPECTION
Yes
No
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No Check Idle air control solenold and wiring harness
=
page FT-147
If OK, go to next step
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has MT, go to next step
Yes Go to next step
Inspect automatlc transmlsslon (AT vehlcles only).
K T
Section K NO Check for cause
Is automatlc transmasion
OK7
Section K
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Fuel Llne Pressure Inspection.
,
I Yes Go to next step
Go to next step
Check resistance of lnjector(s) at PCM connector
If reslstance
IS
OK, check as follows
No
Yes
No
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Yes
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1
Start englne and let Idle to brlng to normal operating
temperature. Does englne stall or RPM drop wlth
idle air control solenold d~sconnected?
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Repair or replace as necessary
Is engine compresslon correct? Yes Go to next step
2
Injector drlve slgnal
Injector flow rate
PCM
No
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Are any dlagnostlc trouble codes
displayed durlng
Key On Englne Off, Key On Englne Runnlng or
Contrnuous Memory rnspectlon?
m
page FT-71
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Check for cause
E *
For 2.3L: Section B1
For 3.OL: Section 8 2
For 4.OL: Section 83
If reslstance
IS
not OK, check for open In Injector
clrcult
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Go to next step
Verlfy test results. If OK, return to diagnostic index to service any add~tlonal symptoms