Mazda MX-5 Miata Sport 2007 Manual page 1981

2007 Mazda MX-5 Miata Sport
2007 ENGINE PERFORMANCE Symptom Troubleshooting - MX-5 Miata
POSSIBLE CAUSE
Idle learning of electronic throttle control

system is not completed
EGR valve malfunction

Erratic or no signal from CMP sensor

Low engine compression

Improper valve timing

Improper variable valve timing control system

operation
Erratic signal from CKP sensor

Improper air/fuel mixture ratio control

operation (abnormal signal form MAF sensor
or HO2S)
Open or short circuit in PCM GND circuit

Poor fuel quality

PCV valve malfunction

Air cleaner restriction

Restriction in exhaust system

Disconnected electrical connectors

Inadequate fuel pressure

Fuel pump body mechanical malfunction

Improper load signal input

Fuel line restriction or clogging

Improper fuel injection control operation

Fuel leakage from fuel injector

Fuel injector clogging

Engine overheating

Vacuum leakage

Pressure regulator malfunction (built-in fuel

pump unit)
WARNING:
The following DIAGNOSTIC PROCEDURE TABLE
contains fuel system diagnosis and repair
procedures. Read following warnings before
servicing the fuel system:
Fuel vapor is hazardous. It can easily

ignite, causing serious injury and damage.
Always keep sparks and flames away from
fuel.
Fuel line spills and leakage are dangerous.
