Legacy Turbo saloon . CEL comes on only when its wet and above 60 mph . Drop below 60 mph and 5 min after it goes off. It only comes on when its raining and never when dry road/conditions prevail. Any ideas please. Car runs perfect, uses no oil, no water, doesnt miss a beat, pulls like holy hell ,idles perfect too Any ideas please you guys would be very much appreciated.

Steve .

Shropshire

 

If it only happens when it's wet then the news isn't particularly good:

My only two guesses are: Water ingress into the wiring somewhere (UH OH!)
Possible problems with the damp air getting into the MAF.

As MAF problems are usually far more dramatic, it looks like your first option is the most likely.

Suggestions:
You could try earthing everything a bit better. This will cost you about £20 and less than an hours time. This may or may not help. As your car runs perfect most of the time, I doubt it will help.

Try inspecting wiring for water ingress when it is raining.
When I get my car back, I'll have a look at places the water could be getting in.

Sorry I can't help more.

 

Not sure if you can read the ECU codes as you can on the Impreza, but if you have a look at this site you might be able to get the error code and see what part of the car is complaining. A Subaru dealer will be able to put a select monitor on your car and tell you what the error is if you can't do it your self.
Cheers.
Ian.

 

diagnostics are the same as impreza turbo.