Is your engine misfiring or surging? Check through the list below:


Engine may be overheating


Check the engine operating temperature. 


 WARNING:  Never try and remove radiator cap when the engine is hot. Allow engine to cool before you carry out any checks.


If is over 115 degrees then the vehicle may overheating. 


If so, check the following:


  • Both fans are wired in properly and are working. 
  • Coolant level low. Top up if necessary. 
  • Engine oil level low. Top up if necessary.
  • Dirt and debris blocking radiator.

  • Check for possible coolant leaks.


Fuel pressure


Check that the fuel pump is working properly and that the fuel flow is smooth and constant.


Ignition system problem


Check and test HT leads connection.


Check and test ignition coil pack to ensure it is working correctly.


Check HT leads for possible moisture, clean and dry if required.


ECU faulty


Use a diagnostics tool to see if there is a fault with the ECU. 


Fuel filter blocked


Check the fuel filters. 


If they are blocked then replace as necessary. 


Vacuum leak


Check brake booster hose for leaks.


Check fuel pressure regulator vacuum hose for leaks.


Check inlet manifold for leaks.


Internal engine failure


Check and test for head gasket failure.


Check and test for possible sticking or damaged cylinder head valve. 


Fuel injection system fault


Check and test for possible electrical injector fault.


Check and test for sticking injector which can cause over fueling. 


Replace if required