Mazda Protege 5. Manual - part 62
ON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM (FS)]
01–02B–68
7
VERIFY CURRENT INPUT SIGNAL STATUS OF
HO2S FRONT
•
Access O2S11 PID using WDS or equivalent.
•
Check PID under following accelerator pedal
condition. (in PARK)
— More than 0.45 V when suddenly
depressing accelerator pedal (rich
condition)
— Less than 0.45 V just after release of
accelerator pedal (lean condition)
•
Is PID reading okay?
Yes Inspect following for air suction due to cracks, damages
and loose parts:
•
From air cleaner to throttle body
•
From throttle body to dynamic chamber
•
From dynamic chamber to intake manifold
•
Vacuum hoses
Note
•
Engine speed may change when rust penetrating
agent is sprayed on the air suction area.
Repair or replace any faulty part, then go to Step 20.
No
Visually inspect for any gas leakage between exhaust
manifold and HO2S (front).
•
If there is no leakage, replace HO2S (front).
Then go to Step 20.
8
INSPECT MAF SIGNAL
•
Start engine.
•
Access MAF PID using WDS or equivalent.
•
Verify that MAF PID changes quickly according
to race engine RPM.
•
Is MAF PID response okay?
Yes Go to next step.
No
Replace MAF sensor, then go to Step 20.
9
INSPECT FOR EXCESSIVE AIR SUCTION OF
INTAKE-AIR SYSTEM
•
Visually inspect for loose, cracked or damaged
hoses on intake-air system.
•
Is there malfunction?
Yes Repair or replace source of air suction, then go to Step 20.
No
Go to next step.
10
INSPECT FUEL LINE PRESSURE
•
Turn ignition key to OFF.
Note
•
If engine will not start, inspect fuel line
pressure with ignition key ON.
•
Inspect fuel line pressure while engine running.
(See 01–14–6 FUEL PRESSURE
INSPECTION.)
•
Is fuel line pressure within 210—250 kPa
{2.1—2.6 kgf/cm
2
, 30—36 psi}?
Yes Go to Step 14.
No
If fuel line pressure is too high: Go to next step.
If fuel line pressure is too low: Go to Step 12.
11
VERIFY VACUUM IS LEADING TO PRESSURE
REGULATOR
•
Disconnect vacuum hose from pressure
regulator.
•
Verify that vacuum is felt at opening port of
disconnected vacuum hose.
•
Is vacuum felt?
Yes Inspect fuel pump maximum pressure and fuel return hose
for clogging.
•
If any problem is found, repair or replace suspected
parts.
•
If all items above are okay, replace pressure regulator.
Then go to Step 20.
No
Verify vacuum hoses are connected correctly.
•
If okay, replace PRC solenoid valve, then go to Step 20.
•
If not, reconnect vacuum hoses to correct position, then
go to Step 20.
12
INSPECT FUEL PUMP MAXIMUM PRESSURE
•
Perform fuel pump maximum pressure test.
(See 01–14–15 FUEL PUMP UNIT
INSPECTION.)
•
Is fuel pump maximum pressure within 450—
630 kPa {4.5—6.5 kgf/cm
2
, 64—92 psi}?
Yes Go to next step.
No
Inspect fuel pump circuit for open or poor connection.
Repair or replace suspected circuit, then go to Step 20.
•
If circuit is okay, replace fuel pump. Then go to Step 20.
STEP
INSPECTION
ACTION
1712-1U-01G(01-02B).fm 68 ページ ２００１年６月２９日 金曜日 午後３時２４分