Check Engine light Causes??

[Chooch]

Wonder what the most common cause for this light to come on?? Emissions
perhaps?? My 2003 Accord has had this problem due to gas cap.. Comments??
TIA

 

[Michael Pardee]

Wonder what the most common cause for this light to come on?? Emissions
perhaps?? My 2003 Accord has had this problem due to gas cap.. Comments??
TIA

I think that is the single most common cause; evaporative emissions fault
(failure of fuel vapor system to create the expected pressure differences).
Beyond that the sky's nearly the limit. Many cars, including Hondas,
piggyback a whole lot of system fault indicators on it to make it a genuine
Malfunction Indicator Light. If the Vehicle Speed Sensor fails completely
you will get the light.

It will *not* report the critical things like loss of oil pressure or
overheating. Those have dedicated indicators for their functions.

Mike

 

[Woody]

All cars since 1996 have OBDII systems as mandated by the EPA. They monitor
all aspects of the emissions systems and if any are out of specs a code is
generated and the check engine light is set. If not fixed some problems will
cause other failures such as destroying the catalytic converter. So if you
have a check light it is a good idea to have the codes read out and find out
the problem. If you live in an area with emissions tests you have to have it
fixed.....