Last week we decided to go to Colorado for Thanksgiving. Checked all fluids before leaving, last check of oil at 750 miles into the trip and about 4500 ft altitude. The car idled rough at 10,000 ft. altitude, also only 85 octane gas and after a couple of days I noticed a burning oil smell. I was only driving about 30 miles a day up there. But every time I stopped it was real strong and visible smoke coming from under the hood.

Prior to coming home I checked the oil and it was TWO QUARTS LOW. Topped it up and checked it every 150-200 miles for the first bit of the drive home, always OK and very little smoke or smell. After crossing Raton Pass the Check Engine Light came on at the first stop sign (now down to about 4,000 foot level. Checked all fluids, etc and all was good. Got gas about 2 hours later, all OK. Also noticed now idling smoothly. Drove another 100 miles to Amarillo, got gas and when I restarted engine, got a short beep and CEL went out. Drove the last 500 miles home, no loss of oil, still some smell of burning oil but showing full on dipstick.

BTW, I checked the obvious places, filter, drain plug, valve cover gaskets, nothing too out of place looking for a car with 75 K miles on it.

Any ideas?

Thanks
Frank

 

I can't think of a connection between altitude and oil leaks...but i love to learn and if someone has any insight, i'd love to hear it.

As for the idle and CEL coming on, some systems are only altitude compensable after the key has been cycled...so...as you increase in altitude atmospheric pressure goes down...atmospheric pressure is an important consideration for fuel calculations and the initial reading may be taken when the key is first turned on and that value will be used throughout the operation during that key cycle. generally, the symptoms will lessen after the key is turned off and then back on at the higher altitude but may not go away completely because there are also special high altitude certifications for vehicles sold in the US. you didn't say what year, make and model your car is so it's hard to tell exactly what the combination of events and calibration is at play here...the same basic ideas apply to the CEL...because of change in atmospheric pressure, some value was changed enough to cause operation outside of a normal parameter, thus causing the CEL and a code to be set...having the code checked will lend more insight to the bigger picture. not having it checked is no big deal...it will eventually clear on it's own if it's 96 or newer...and all normal operating conditions have been restored so don't panic about the light...i sure would keep an eye on the oil leak thing tho...perhaps even have it raised up, that much oil leaking out should have left some evidence as to where it came from...good luck

 

Sorry carguy, I had typed in all the specs, then I typed something else over them

It's a 1998 Subaru Forester L, Automatic, 1.6 Boxer type engine.

I know several cars have had "loose" gas caps causing CELs but I wasn't aware that on newer cars the light would reset itself without me disconnecting the batter and standing on the brake pedal.

I drove the 1100 miles home without any lose of oil. Next day I drove to the car wash and used the high pressure spray all over the engine. I've only driven it about 50 miles since then but there is no evidence of the leak and I'm not getting the smell since cleaning the engine. I have to put about a 120 mile round trip on it Saturday tho and that should show up any leaks.

Yep, I understand about the altitude changes. I'm old enough to remember the first time we drove to Colorado in my Dad's l960 Chevy having to reset the points, timing and carb to drive up Pike's Peak, I sure do love the "learning" computers in newer cars.

Wife says it may be time to move this unit out even though it's only 5 years old, much as we like it I'd like to get my Maxima back from her, she starting to act like it's her car.

Frank

 

Check to see if it is weeping out oil from the valve covers or out of the front or rear crankshaft oil seals. Getting a UV light and adding UV dye to your oild will greatly help you in pinpoting the origin of the leak.

Zzyzzx

 

...two quarts low in a few hundred miles!

 

Carguy
I found my notes from the trip, it looks like the two quarts went in about 400 miles, even that is a bit weird. I drove the car home (1100 miles) with no loss of oil and put another 100 or so on it here. No loss of oil and my wife drove about 20 miles this morning and noticed no smell of burning oil, and her nose is at least as sensitive as mine.

I've jacked around with cars for about 40 years and this is just WEIRD. I think I'll quit worrying about it.

Frank

 

Hi, I was researching a problem with my 95 legacy and came upon this thread so it inspired me to join. Same thing as frank sez: drive 60 or 70 hard miles and see a huge cloud of smoke when I stop (and I mean huge) and down 2 quarts then drive hundreds with no problems or oil loss. Its been this way for several years albeit has gotten a little worse lately. I know they are notorious for all kinds of engine seals going at 90k or so. Im thinking it's dripping on the CAT and runs off while driving but collects and burns off when I stop. No explanation for the sporadic. Any body think this could be dangerous?

My CEL is not on by the way but I had a 92 Loyale I drove for 85K with that on and im sure its still tapping its way around with that light on!

 

if it is dripping on the cat it is a fire looking for a place to happen, sounds like maybe engine rings are lining the gaps up and allowing oil to enter the engine, boxer engines can do that sometimes because the oil level occasionally will be above the bottom of the piston on slopes or hard corners.

life begins when the kids leave home and the dog dies