Engine warning lights and dirty oil

Had an issue with “check” engine light turning on and “cruise” control light flashing, intermittently. Dealer said we had dirty oil contaminating some solenoid valves in the system but we had just done an oil change and do so every 3-5K (car has 170K). They recommended switching around the sensors and doing an “oil flush” with another oil change @ $280.00. The warning light problem hasn’t recurred, in the past month, since we started giving the gas cap a few extra turns after a fill-up.
We’re getting ready to buy a new car and don’t want to give what might be a serious problem over to the next owner. Has anyone ever heard of the repair recommended ??

The dealer was just guessing, I believe, and took advantage of your ignorance to sell you something you probably don’t need. If there was a problem, the dealer certainly did not know what it was.

Not tightening the gas cap will cause the engine light to illuminate. I would not worry about a possible problem here; your car has been maintained better than most, and the next owner will have many happy years of driving.

I would just stop doing any business with this dealer, and shop elsewhere.

Tagged: Subaru Legacy
(car has 170K)

Model-Year ?

Provided Information Is Weak.
The Dealer Was Talking About Engine Oil And Not Transmission Fluid (Oil) ?

It Would Be Helpful For You To Provide More Specific Information About " some solenoid valves in the system "

What valves ? What system ?

The dealer is possibly giving you a resonable option.

Did You Get A Good Understanding Of The Situation ?
If you can’t furnish sufficient information then advice you get will be not be very helpful.


@commonsenseanswer The dealer might have been talking about solenoids for the variable valve timing. Those can certainly get gummed up due to infrequent oil changes, and even using the wrong viscosity oil.

@db4690, Thanks, I Hadn’t Considered Those Overly Complicated Valve Trains. I’ve Not Owned A Machine With That Set-Up (Purposely).

@commonsenseanswer unfortunately, at some point in time, even the majority of used vehicles will have variable valve timing.