condition.
Is the spark plug wet,
covered with carbon or
grayish white?
with carbon:
Inspect for fuel leakage from
injector.
Spark plug is grayish white:
Inspect the fuel injector for
clogging.
No
Install the spark plugs on
original cylinders.
Go to the next step.
11
Perform the electronic
throttle control system
operation inspection.
(See
ELECTRONIC
THROTTLE
CONTROL SYSTEM
INSPECTION
.)
Does the electronic
throttle control system
function properly?
Yes
Go to the next step.
No
Repair or replace the
malfunctioning part according to
electronic throttle control
system operation inspection
results.
12
Install fuel pressure
gauge between fuel pipe
and fuel distributor.
Start the engine and run
it at idle.
Measure fuel line
pressure during idle.
Is fuel line pressure
correct during idle?
(See
FUEL LINE
PRESSURE
INSPECTION [LF]
.)
Yes
Go to the next step.
No
Low:
Inspect the fuel line for
clogging.
If there is no malfunction,
replace fuel pump unit.
(See
FUEL PUMP UNIT
REMOVAL/INSTALLATION
[LF]
.)
High:
Replace the fuel pump unit.
(See
FUEL PUMP UNIT
REMOVAL/INSTALLATION
[LF]
.)
13
Visually inspect for fuel
leakage at fuel injector,
O-ring, and fuel line.
Service if necessary.
Does fuel line pressure
hold after ignition
switch is turned off?
(See
FUEL LINE
PRESSURE
INSPECTION [LF]
.)
Yes
Go to the next step.
No
Inspect fuel injector.
If fuel injector is normal, replace
fuel pump unit.
14
Connect the M-MDS or
equivalent to the DLC-
2.
Yes
Go to the next step.
No
LONG FT1 PID is out of
specification.
2007 Mazda MX-5 Miata Sport
2007 ENGINE PERFORMANCE Symptom Troubleshooting - MX-5 Miata
Microsoft
Thursday, July 09, 2009 2:42:10 PM
Page 52
© 2005 Mitchell Repair Information Company, LLC.