Check Engine light comes on due to a wide range of possible problems, often automatically disabling the cruise control, leaving it blinking. The problems can range from sensor issues (MAF, Oxygen Sensors, Etc.) to a loose gas cap, to condensation, to a loose connector on a sensor, perhaps even a dying battery, a flaky alternator or a faulty battery terminal connection. It is a catch-all problem indicator. If you are lucky, you can simply reset the ECU by disconnecting the battery for a minute, and the Check Engine light will be gone and cruise control will work. If the error persists, you need to get the error code (if you do not have a code reader or accesspoint, stop by Autozone or somewhere similar and get them to read it for you) see what the error is, and fix the problem. Simple? Hopefully it's not something more troublesome, bad injector, etc.
your engine is stuffed
yes
With the proper scan tool.
Check this site for information: http://www.troublecodes.net/Subaru/
why the engine light of my subaru came on after i washed the engine
Not necessarily.
If you take your subaru to Parts plus or an automotive store you can usually have them hook up their computer to the side panel, in the dash board of your car and it will give them a code. The code will tell you exactly why the check engine light is on.
Most auto parts stores have a check engine light reader that you can borrow for free to read the code and also to reset the check engine light. If they are not busy, they may even do it for you for free. Support your local parts store! Worst case: Take it to your dealer or buy a check engine light reader that can also reset it.
After repairing the cause of the code, you can clear it with a scan tool.
take earth of batt for 5 mins an then put it back on an it resets it
make sure when putting gas cap back on that you tighten the cap until it clicks or the check engine light will ccome on
Electronic Controlled Suspension. That's a nice thought, but, I'm pretty sure this is Subaru's version of the 'Check Engine' light. Electronic Stability Control