Mazda MX-6 1998, Workshop Manual

Page: 203 / 1282

TROUBLESHOOTING [ENGINE CONTROL FS]
Pressure Regulator Control Inspection
Warning
• Fuel line spills and leaks are dangerous.
Fuel can ignite and cause serious injuries
or death and damage. Fuel can also irritate
skin and eyes. To prevent this, always
complete the “BEFORE REPAIR
PROCEDURE” and “AFTER REPAIR
PROCEDURE”. (Refer to 01-14 BEFORE
REPAIR PROCEDURE, 01-14 AFTER
REPAIR PROCEDURE.)
1. Install the fuel pressure gauge.
Specifications
Fuel pressure (kPa {kgf/cm2, psi})
Idling
210— 260
{2.1— 2.6,
30— 37}
210— 260
{2.1— 2.6,
30— 37}
260— 310
During 120 sec.
of hot start
260— 310
{2.6— 3.2,
37—46}
37—46}
After 120 sec. ot
hot start
210— 260
{2.1— 2.6,
37— 46}
210— 260
{2.1— 2.6,
30— 37}
260— 310
{2.6— 3.2,
37—46}
Pressure
regulator control
condition
Normal
Not normal
(Perform
Inspection 1)
Not normal
(Perform
Inspection 2)
3. If the fuel pressure is not within the specification,
carry out either Inspection 1 or Inspection 2 as
required.
Inspection 1
1. Connect the SSTs (NGS tester) to the DLC.
2. A c c e s s th e fo llo w in g P ID s.
• E C T PID . (R e fe r to 0 1 - 4 0 A E N G IN E
C O O L A N T T E M P E R A T U R E S E N S O R
IN S P E C T IO N [F S ].)
• IAT PID . (R e fe r to 0 1 -4 0 A IN T A K E A IR
T E M P E R A T U R E S E N S O R IN S P E C T IO N
FS].)
• T P V P ID . (R e fe r to 0 1 -4 0 A T H R O T T L E
P O S IT IO N S E N S O R IN S P E C T IO N [F S ].)
3. C h e c k P ID va lu e .
4. If okay, c h e c k :
• Pressure regulator.
• P R C s o le n o id va lve .
• W irin g b e tw e e n P R C s o le n o id v a lv e a n d P C M
te rm in a l 19 (o p e n c irc u it).
• W irin g b e tw e e n m ain re la y a n d P R C s o le n o id
v a lv e (o p e n c irc u it).
Inspection 2
1. C o n n e c t th e
S S T s
(N G S te s te r) to th e D LC .
2. Access the following PIDs.
• ECT PID. (Refer to 01-40A ENGINE
COOLANT TEMPERATURE SENSOR
INSPECTION [FS].)
• IAT PID. (Refer to 01-40A INTAKE AIR
TEMPERATURE SENSOR INSPECTION
[FS].)
3. Check PID value.
4. If okay, check:
• Loose or damaged vacuum hose between the
pressure regulator, PRC solenoid valve, and
intake manifold.
• PRC solenoid valve.
• Wiring between PRC solenoid valve and PCM
terminal 19 (short circuit).
IN S T A LL C L A M P S
W6U101WB0
2. Measure the fuel pressure under the following
conditions:
0 1 -0 1 A -1 75