My Toyota Corolla engine suffered a broken a timing belt

Hello Paul, Iam Baguma from Isingiro. My Toyota Corolla with a 5A engine suffered a broken a timing belt. My mechanic replaced the timing belt and the car was test driven. However, it soon developed an engine failure to start. The mechanic has replaced the fuel pump and now says it’s the distributor. What do you think is the cause of this problem?

Hello Baguma, there are several factors that can lead to failure of an engine to start. Broadly I will categorise them into: engine management system, fuel system, ignition system and air intake system. The engine management system (EMS) relies on the engine computer to control the amount of fuel injected and ignition timing.

This system relies on sensors such as the crank shaft position sensor, camshaft position sensor and coolant temperature sensor to help it know when to deliver sufficient fuel and spark for efficient engine combustion. A break down of any of these sensors can prevent the EMS from starting the car or running smoothly.

The EMS performance and health can be investigated with a computer diagnostic tool.
The fuel system delivers sufficient fuel pressure for prompt ignition. I see your mechanic has looked into it by replacing the fuel pump.

A faulty fuel pump can cause a no start condition. Did your mechanic fit a new pump and has he measured the fuel pressure and compared with recommended values? The fuel filter should be replaced and the performance of fuel injectors also be assessed. The ignition system in your Toyota 5A petrol engine generates a spark or heats an electrode in the spark plugs to ignite the fuel air mixture.

This system on your car engine works with the distributor which allocates the spark, ignition high tension leads and the spark plugs. These three must be investigated to ensure that they work well.

Having replaced the engine timing belt it may be a good idea to confirm that the engine timing was correctly done using the manufacturers’ timing reference marks. Failure to get the timing right, either retarded or advanced will affect ignition or spark timing.

This can prevent prompt starting or cause poor performance. It is also prudent to confirm that the distributor was timed well and not damaged after timing belt renewal. A compression test is also in order to confirm that there is sufficient compression to start and run the engine.

The air intake system is broad but investigate the intake hoses for air leak between the air filter and throttle potentiometer. Inspect the throttle potentiometer for not.al operation and rule out a carbon clogged or stuck throttle valve.

Sufficient in restricted air affects the prompt ignition of any car. You need a patient and knowledgeable mechanic to investigate.