Honda TRX500 Foreman Rubicon Won’t Start (2005-2012)

Honda TRX500 Foreman Rubicon Won’t Start 2012 2011 2010 2009 2008 2007 2006 2005

If the Honda TRX500 Foreman Rubicon won’t start and being to work, or if the four-wheeler has a hard time starting up, use the following troubleshooting guide to pinpoint the cause of the starting problem.

1. Does fuel reach the carburetor?

If fuel is not reaching the carburetor, check for a clogged fuel line or strainer, faulty fuel valve or clogged fuel tank breather hose. If fuel is reaching the carburetor, check spark plugs.

2. Spark plug inspection.

Remove the spark plug and to see if the spark plug is wet. If the spark plug is wet, check for one or more possible malfunctions:

  • Flooded carburetor
  • Throttle valve open
  • Dirty air cleaner
  • Improperly adjusted pilot screw
  • Starting enrichment (SE) valve stuck open or damaged

If the spark plug is not wet, does it have spark?

3. Spark test.

Perform a spark test. If there is no spark or the spark is weak, check for one or more possible malfunctions:

  • Faulty ignition switch

  • Faulty engine control module (ECM)
  • Faulty spark plug

  • Loose or disconnected ignition system wires
  • Broken or shorted spark plug wire

  • Faulty ignition pulse generator

  • Faulty ignition coil

  • Faulty engine stop switch

  • Fouled spark plug


If spark is good, check engine starting condition.

4. Engine starting condition.

Attempt to start the engine following the normal operating procedures outlined in the owner’s manual. If the engine starts up but then stops or stalls, check for one or more possible malfunctions:

  • Contaminated fuel
  • Improper SE valve operation
  • Leaking carburetor insulator

  • Incorrectly adjusted carburetor
  • Improper ignition timing (Faulty ECM or ignition pulse generator)


If all components are in good working order, check cylinder compression. Be certain you adjust idle rpm. 

5. Cylinder compression.

Test cylinder compression pressure. If the compression is too low, check for one or more possible malfunctions:

  • Improper valve timing
  • Valve clearance too small
  • Valve stuck open
Worn cylinder and piston rings
  • Damaged cylinder head gasket
  • Seized valve

Use the above mentioned troubleshooting guide if the TRX500 won’t start. These procedures are also outlined in the factory service manual. It’s recommended to download the factory service manual when performing service, repair and maintenance to the all-terrine vehicle. Repair manuals can be downloaded from this site.

These troubleshooting procedures apply to: 2005 2006 2007 2008 2009 2010 2011 2012 Honda TRX500FA FourTrax Foreman Rubicon, TRX500FGA FourTrax Foreman Rubicon GPScape, TRX500FPA FourTrax Foreman Rubicon GPScape Power Steering, TRX500, TRX 500 models. 

Be the first to comment

Leave a Reply

Your email address will not be published.


*