Oil Light Mystery in a 97 legacy obw

[Mike G.]

Hello,

I have a 1997 legacy outback 5speed that has started showing me how bright the oil light can get.

 

About 2 weeks ago I changed the oil and filter with a fram filter and castrol gtx 10-30 oil. I average about 120 miles a day commuting so it doesn't't take long to hit 3K for an oil change.

 

At random intervals from a cold start my oil light will come on during my drive, and it will go out at random RPM's while driving.

I thought maybe I had gotten a bad filter so I changed it out with no effect at all.

I have no symptoms of overheating, or anymore valve-train noise than the engine had since I bought the car. I have put on about 15K miles since I purchased the car.

 

I don't know the history of the car, but could it be possible that getting a series of regular oil changes since I bought it has loosened up some sludge in the motor and partially plugged up the oil passages in there?

 

Would a Sea-foam and/or MMO treatment help or hurt?

 

Thanks,

Mike G.

[cookie]

You need to put a manual oil pressure guage on it to test what is really happening. You could have blown an oil pump o ring or have something as simple as a bad sender or short. If it were mine I'd be on the way to the auto parts store now.

[uniberp]

If it flickers on at idle, it's probably low pressure due probably to worn bearings.

 

If it flashes on at speed, it's probably an electrical connection.

 

 

Hello,

I have a 1997 legacy outback 5speed that has started showing me how bright the oil light can get.

 

About 2 weeks ago I changed the oil and filter with a fram filter and castrol gtx 10-30 oil. I average about 120 miles a day commuting so it doesn't't take long to hit 3K for an oil change.

 

At random intervals from a cold start my oil light will come on during my drive, and it will go out at random RPM's while driving.

I thought maybe I had gotten a bad filter so I changed it out with no effect at all.

I have no symptoms of overheating, or anymore valve-train noise than the engine had since I bought the car. I have put on about 15K miles since I purchased the car.

 

I don't know the history of the car, but could it be possible that getting a series of regular oil changes since I bought it has loosened up some sludge in the motor and partially plugged up the oil passages in there?

 

Would a Sea-foam and/or MMO treatment help or hurt?

 

Thanks,

Mike G.

[cookie]

A friend just had his oil pump check valve go and do the high speed thing. Engine seems to have been saved though.

Just running a lighter oil can cause flicker at idle and I have heard of weird light stuff on Subies when the alternator goes too.

[Commuter]

You need to put a manual oil pressure guage on it to test what is really happening. You could have blown an oil pump o ring or have something as simple as a bad sender or short. If it were mine I'd be on the way to the auto parts store now.

I'm with cookie here. It's also possible that the backing plate on the oil pump is loose. The screws are known to back off slightly on these models and cause a gradual drop in pressure. A good shop / dealer will know of this and address it during a timing belt change, along with the O-ring. When was the timing belt last done?

 

You don't want to be driving with low oil pressure (if indeed, this is the case). Bad things can happen quickly.

 

Also, I'd recommend a filter other than Fram. Go Purolator if you don't want to buy dealer oil filters.

 

Commuter