Page 291 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

LESSON 85 & 86 : Tune up the engine with the help of

multi scan tool, adjusting of valve
tappet clearance checking and setting

at injection timing & valve timing

Objectives

At the end of this lesson you shall be able to
• tune up the engine with multi scan tool.
• adjust Tappet clearance
• setting Vale timing and Injection timing.

Tune up the engine with the help of multi scan tool

Below are the steps to tune the engine with the help of Multi Scan Tool
• Connect the multi-scan tool: to the vehicle’s OBD-II port, which is usually located under the dashboard on
the driver’s side. Carefully plug in the multi-scan tool.
• (DTC) Read Diagnostic Trouble Codes: Read stored diagnostic trouble codes using the multi-scan tool.
These codes indicate potential problems with various engines.
• Live Data Check: Access multi-scan tool live data to monitor real-time engine parameters such as fuel trim
level, engine speed, coolant temperature, oxygen sensor readings.
• Analyze Data: Analyze live data to identify any anomalies or areas where engine adjustments may be needed.
Pay attention to fuel trim parameters, which may indicate the engine is running too low or too fast.
• Adjust parameters: Depending on the data analysis, various engine components may need to be adjusted.

Spark Plugs: Replace damaged spark plugs with new ones to ensure proper ignition
Ignition Timing: Use the Multi-Scan tool to adjust ignition timing as necessary for optimal performance.
Fuel Injectors: Clean or replace fuel injectors if you want to improve fuel delivery and efficiency.
Air/Fuel Mixture: Adjust the air/ fuel mixture based on oxygen sensor readings to achieve the ideal ratio for
combustion.
• Monitor changes: After adjustments have been made, monitor the live data again to ensure that engine
efficiency has improved as a result of the changes. Performance also improved.
• Clear DTC: After the tuning procedure is complete and the problem has been resolved, clear any stored
diagnostic trouble codes. Use the multi-scan tool to clean.
• Test Drive: Engine running smoothly. Take the vehicle for a test drive to verify that the previous issues have
been resolved.
• Final Check: Reconnect the multi-scan tool to recheck the engine parameters if any residual problems or
abnormalities occur.
Adjusting of valve tappet clearance checking and setting at injection timing & valve timing
Adjusting the valve tappet clearance: It is important to check the clearance and calibration of valve to avoid
noise, loss of power as well as less fuel consumption with excessive emission of pollutants.
Through these problem, the engine manufacturers suggest to identify the valve timing problem.
It is also called tappet clearance. The clearance is given between the top face of valve stem and rocker arm tip
when valve is closed. As shown in given fig.

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