"Check Engine" Solid - Flashing "Cruise" '05 Forester

how's the speedometer workin'....cause perhaps the VSS is faulty~ 'cruise' light's a new one to me...gonna have to investigate what brings this one on...one might surmise that the throttle wants to be controlled by the computer...is controlled by the speed sensor and the switch on the brake pedal...are you in Alameda county? Lake county seems to be a little more lax because ALL the SMOKERS are both smokin' cigarettes and the cars are smokin' too...with their mismatched body panels and busted glass~

....and a tatoo instead of gettin' that one tooth fixed~

Go have the OBDII codes read with a scan tool the next time it does this because that's the one sure way to find out what's going on.

With that year Forester, it blinks the cruise light alongside the check engine light. Do what Nick says, the issue sounds like an evap code.

Can winter-blend fuel (or switching between summer and winter blends) be causing issues with the Subaru sensors? The premium gas seems to have kept the issue from returning. I'll switch back to regular next time I fill the tank and see if the warning lights return. The car is running as smooth as ever. No speedometer issues (Judge_Roy)... and we have all of our teeth in our corner of Southern California... most of us...

The code is probably still saved and could be checked with a code scanner, even if it is not currently active. It's hard to determine the possible cause and solution without having the actual code, but in my experience the evap codes don't go away dependent on fuel types.

Jeff, The code was saved: P0420 Catalyst Efficiency Below Threshold (Bank 1) The code reader said the O2 sensor and the Cat Converter were OK The "Check Engine" and flashing "Cruise" lights are still off - haven't yet switched back from the premium gas - will do on the next fill-up and see if the "Check Engine" and flashing "Cruise" return.

That code is for either the O2 or the cat, more than likely the O2 sensor. I've had them be sporadic like that before, and more than likely it'll get more frequent eventually. In any case, you're fine to not worry about it in the meantime.

My front differential oil was a little low (Just replaced)... could that have been the source of the P0420 ? ... just replaced fuel cap on as well. I'm now about half a tank into a lower octane fuel & the check engine / flashing cruise lights have yet to return. I'm guessing Jeff (Thanks, Jeff) is right about the O2 sensor - though I've read about people having the same issue and throwing a bunch of cash at the problem (O2 / MAF sensors, Cat. Converter) and not having positive results. I'll wait until the lights return then go from there.

No problem. Your differential fluid level wouldn't have anything to do with the P0420 code. I wouldn't worry about it unless it comes back.

I answered in more detail in another thread - but basically, the Subarus seem to be very sensitive to low oil pressure, and a dirty oil filter might be the only problem. Some of the lights reset automatically, which is why the problem "goes away". But after a while, something happens that reduces oil flow enough to trip the "low oil pressure" alarms and on comes the Christmas tree again. Easy to buy a new one and find out!.

This has happened twice recently to my 2007 forester. Each time, I disconnect the battery, reconnect, then everything is fine. Not sure what the cause is though.

I had this exact issue occur today. Disconnected battery for about 10 seconds and issue resolved. While I am across the country on vacation, I am visiting family with tools!

Sharon1934, I think I solved the problem. My battery was weak and in need of replacement. Once I did this, this problem stopped. Is your battery old? If so, that might be your problem. DTOR

A couple days after this, drove about 60 miles and the same happened again, no cruise control. Before returning home,went to fill up. Tank would not accept gas! Significant since I was more than 100 miles from my parent's where I was visiting , slated to drive 750 m following day and less than 1/4 tank. Turned to Subaru roadside assist, they located authorized repair center about 5 miles away. Turned out to be solenoid, two days for parts. Covered by warranty with loaner available. Could have been worse than messing up vacation so will count blessings.

Ps...battery less than a year old