8. Warm up the engine and idle it.
9. Apply battery voltage to the oil control valve (OCV) and verify that the engine idles roughly or stalls.
If the engine idles roughly or stalls, inspect the timing belt component (valve timing deviation).
If the engine does not idle roughly or stalls, go to the next step.
10. Remove the oil control valve (OCV) and perform spool valve operation inspection.
(See
OIL CONTROL VALVE (OCV) INSPECTION [LF]
.)
If not as specified, inspect the following:
Oil control valve (OCV)
Harnesses and connectors between oil control valve (OCV) and PCM open or short.
If as specified, inspect the following hydraulic passages for clogging or leakage or both:
Oil pressure switch-oil control valve (OCV)
Oil control valve (OCV)-camshaft
Camshaft internal passage
11. If they are normal, replace the camshaft pulley (with built-in variable valve timing actuator).
EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK INSPECTION
To verify that the problem has been fixed properly after repairs, the run drive cycle or EVAP system leak
inspection must be performed.
EVAP System Leak Inspection Using M-MDS or Equivalent
EVAP System Test Description
The EVAP system test finds gas leaks in the system using the PCM to monitor changes in the air pump
load current of the EVAP system leak detection pump. This test starts after sending an on-demand test
signal from the M-MDS to the PCM. The PCM controls the air pump and change-over-valve operation
and also stores the load current of the air pump as follows:
i. The PCM commands turn the air pump on and retrieve the air pump load current value (LDP_MON
PID) as a reference current (LDP_REF PID).
ii. After retrieving a reference current value, the PCM commands the change-over-valve to open, then
captures the air pump load current value (LDP_MON PID) as idle current (LDP_IDL PID). The
EVAP system will be pressurized from this phase.
iii. The PCM continues to monitor the air pump load current value (LDP_MON PID) until the end of
NOTE:
EVAP system test outline
The EVAP system test, which can substituted for the run drive cycle as an
EVAP control system repair confirmation method, can be done while
operating the M-MDS in the KOEO (Key On Engine Off) condition instead
of actually driving the vehicle.
2007 Mazda MX-5 Miata Sport
2007 ENGINE PERFORMANCE Symptom Troubleshooting - MX-5 Miata
Microsoft
Thursday, July 09, 2009 2:42:11 PM
Page 145
© 2005 Mitchell Repair Information Company, LLC.