No Comments

Car Engine Running Rough – Mechanic Enoggera

Todays vehicle computers rely on correct and accurate data from electronic sensors (inputs).

The critical sensors measure air (air coming into the engine) and load (throttle position) at different conditions… ie going up or down hills, power mode like overtaking or start, stop city driving. This data is fed to the computer. The computer looks up the appropriate tables and then activates the fuel injectors to correspond to the required conditions in milliseconds (outputs). The fuel is delivered from a high pressure fuel pump – through the opening of the injectors which are then rapidly closed. The comparison of when a fuel injector is turned on as to when it is turned off is known as a duty cycle.

The computer also activates the ignition coils which generate high voltage spark to ignite the fuel mixture in the engine. The computer can control the spark timing to be more advanced or retarded according to engine load.

The exhaust gases are also measured by the computer via an oxygen sensor situation in the exhaust. This information fed back to the computer is known as a closed loop system.

This closed loop system working correctly minimises emissions, when an engine light comes on, this means that there is a fault and emissions are above the correct settings – this must be rectified immediately.

At Mannys Mechanical Repairs we are constantly training to keep up with this technology and possible faults that can occur. We spend thousands of dollars in the latest equipment and training.

• We check battery condition – which is vital to computer reference.
• We check alternator charge rate, diode testing for any spikes.
• We perform cylinder balance testing and perform electronic compression tests when required.
• Check fuel trim operations and evaluate the information the fuel trim gives which also leads to oxygen sensor performance testing.
• Perform full electronic scan on engine, transmission, body modules, antilock braking systems.
• Check for any generic OBD2 (on board diagnostics 2) faults.

The art of tuning is done within the computer. But at Mannys Mechanical we have the skill and the equipment to analyse and check that your vehicle is running to optimum performance.

– Manny, 0411 496 621
To serve, to perform, to guide.

At Manny’s Mechanical Repairs you are in good hands, our main services include, Safety CertificatesLogbook ServiceFree Pickup & Delivery, and Car Cooling System Repairs.


We have the latest diagnostic equipment and my work van is fitted out with an industrial air compressor. This enables me to perform heavy duty work and give you – the customer – the best service at any place and at any time.

For Bookings and enquiries, please contact us on 0411 496 621email us at or visit our site