Adaptive Fuel Control - Mazda B-Series 1997 Workshop Manual

P I
ON-BOARD DIAGNOSIS SYSTEM
Diagnostic trouble code ADAPTIVE FUEL CONTROL
No. P0171, P0172, P0174,
P0175, P1130, P1131, P1132,
P1150. P1151. PI152
Symptom
---
Fuel adaptive system is at rlch correction limit due to fuellair ratlo too lean.
Fuel adaptive system is at lean correction limit due to fuellair ratio too rich.
Fuellair ratio is correcting for an overly-lean condition.
Fuellair ratio is correcting for an overly-rich condition.
Fuel control has reached ~ t s maxlmum compensation for lean or rich and H02S is not
switching.
INSPECTION ACTION
Check air intake for leaks, blockage or vacuum leak.
Check integrity of PCV system.
Check for improperly seated dipstick.
Are there any of the above concerns?
Yes Repair as necessary.
Go to step 25.
2
j
NO
GO to next step.
Key OFF.
Connect scan tool or NGS to data link connector.
Disconnect fuel vapor hose from intake manifold and plug
fitting at intake manifold.
Run engine at 2000 rpm for 1 minute and return to idle.
Perform KOER self-test.
Are DTCs P1131, P1132, PI151 or PI152 present?
L
. .
I
Yes Go to next step.
1
No For DTC P1130, P1150, P0171, P0174,
I
i
PO1 72 and PO1 75:
Go to next step.
If PI132 andlor PI152 are no longer
present:
Reconnect fuel vapor line and go to step 1
of pinpoint test for DTC P1443.
For all others: Go to "Intermittent Concerns."
=
pane FT-69
I
Key OFF. Yes Go to next step.
Install fuel pressure gauge.
Verify vacuum source to fuel pressure regulator.
If engine will start:
Record fuel pressure at ~dle.
-
Increase engine speed to 2500 rpm and maintain for One
'
N , Perform "Fuel Line Pressure Inspection,"
minute. Record fuel pressure.
G=
page FT-150
If no start:
Cycle key on and off several times. Record fuel pressure.
Is fuel pressure between 240-280 kPa (2.5-2.8 Kgf/cm2,
1
35-40 psi)?
,
4 Leave fuel pressure gauge connected
Yes For DTCs P1130, Pl150, PO1 71, P0172,
Cycle key on and off several t~mes.
PO1 74 and PO1 75:
Verlfy that there are no external leaks.
Go to next step
Does fuel pressure remain w~thln 5
PSI
of h~ghest readlng
,
For No Starts:
after one rnlnute?
Go to step 6
For fuel control DTCs displayed with
I
misfire DTCs:
I
Go to step 7
All other DTCs:
Go to step 11.
5
6
Was there a pressure drop greater than 5
PSI?
I
22:",',"'
step.
'
No Perform "Fuel Pressure Hold Inspection."
j
=
page FT-150
Leave fuel pressure gauge connected
Cycle key on and off several t~mes.
Turn key on, englne
off
Does the fuel pressure remaln wrthrn 5
PSI
of the h~ghest
readlng after 10 seconds?
Leave fuel pressure gauge connected.
Cycle key on and off several tlmes
D~sconnect Inertla fuel shut-off sw~tch connector.
Mon~tor pressure gauge whlle crank~ng englne for at least
NO
1
R c ? ~ ~ ~ n e c t Inenla fuel shut-off switch
flve seconds.
Yes For DTCs P1130, PI1 50, PO1 71 and PO1 74: ,
Go to step
7
NO For DTCs Po172 and P0175:
Go to step 9.
Yes EEC-V system
IS
not the cause of the no
/
start. Return to "D~agnostlc Index" chart