Diagnostic Procedure
WARNING: This page is about a different car, the 2005 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.
NO.15 EMISSION COMPLIANCE [BP, BP WITH TC] DIAGNOSTIC PROCEDURE
| STEP |
INSPECTION |
ACTION |
| 1 |
- Inspect following:
- Vacuum lines for leakage or blockage
- Electrical connections
- Proper maintenance schedule followed
- Intake-air system and ACL element concerns: obstructions, leakage or dirtiness.
- Are all items okay?
|
Yes |
Go to the next step. |
| No |
Service if necessary.
Repeat Step 1. |
| 2 |
- Connect WDS or equivalent to DLC-2.
- Turn ignition switch to ON.
- Retrieve any DTC.
- Is "PASSED" displayed?
|
Yes |
No DTC displayed:
|
| No |
DTC displayed:
- Go to appropriate DTC test.
|
| 3 |
- Is any other driveability concern present?
|
Yes |
Go to appropriate flow chart. |
| No |
Go to the next step. |
| 4 |
- Connect WDS or equivalent to DLC-2.
- Access ECT PID.
- Warm up engine and run it at idle.
- Verify ECT PID is correct.
(See PCM INSPECTION
)
- Is ECT PID correct?
|
Yes |
Go to the next step. |
| No |
Inspect for coolant leakage, cooling fan and condenser fan operation or thermostat operation. |
| 5 |
- Is strong blue spark visible at each disconnected high-tension lead while cranking engine?
|
Yes |
Inspect for following:
- Spark plugs malfunction
- CMP sensor is improperly installed.
- Damage of trigger wheel on camshaft
- Open or short circuit on CMP sensor
- Open or short circuit between CMP sensor and PCM terminal 3V
Repair or replace malfunctioning parts.
- If okay, go to the next step.
|
| No |
Inspect following:
- High-tension leads
- Ignition coil and connector
|
| 6 |
- Install fuel pressure gauge between fuel filter and fuel distributor.
- Start engine and run it at idle.
- Measure fuel line pressure at idle.
- Is fuel line pressure correct at idle?
Fuel line pressure 370-420 kPa {3.7-4.3 kgf/cm2, 53-61 psi} |
Yes |
Go to the next step. |
| No |
Zero or low:
- Inspect FP circuit.
- Inspect for open FP relief valve.
- Inspect for fuel leakage inside pressure regulator.
- Inspect for clogged main fuel line.
- Inspect pulsation damper.
High:
- Inspect pressure regulator for high pressure cause.
- Inspect for clogged fuel return line.
|
| 7 |
- Remove and shake PCV valve.
- Does PCV valve rattle?
|
Yes |
Go to the next step. |
| No |
Replace PCV valve. |
| 8 |
- Inspect for fuel saturation inside charcoal canister.
- Is excessive amount of liquid fuel present in canister?
|
Yes |
Replace charcoal canister. |
| No |
Go to the next step. |
| 9 |
- Is there restriction in exhaust system?
|
Yes |
Inspect exhaust system. |
| No |
Inspect EGR system. |
| 10 |
- Verify test results.
- If okay, return to diagnostic index to service any additional symptoms.
- If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
- If vehicle is repaired, troubleshooting completed.
- If vehicle is not repaired or additional diagnostic information is not available, replace PCM
|