Low Oil pressure!!

[Atoz]

I have a 2009 128i that I've owned since new with 87K miles that I have never had problems with until I got an MIL for misfires. I replaced the VANOS solenoids (with gaskets) as I've read that they're a common failure and installed new plugs since it's due anyway; The car continued to misfire. I let the car sit for about a week while I researched the issue and didn't want to continue driving it with the MIL on.

One night, I decided to take the car out to keep the battery charged as it was cold that night, the temp read 19 deg F when I got in the car. It started right away and as I was beginning to put it in gear I got a low oil pressure light. I immediately shut the engine down and then restarted and the light came back. I was fairly certain the level was good because I check it regularly, but with no dipstick I couldn't confirm.

I did some research and began thinking that there may be some water in the oil due to condensation since I work on a smoke free campus and we have to drive off property to smoke so there are a LOT of short trips. I decided to leave it alone until the weather got warmer to drain and refill the oil.

Last night it was in the mid fifties so I ran another test start and the light came back. When I drained the oil water came out; about a pint, maybe more, maybe less. It was clear so I don't think it's coolant and when I took my glove off it wasn't slippery like coolant should be, the coolant was full and no oil present - again I was thinking condensation, but that would be a LOT of condensation. The oil drain went right to the top of a 7 Qt. pan, I put 6.5 quarts of Mobil 1 5w20 in it as I already had a case for my other car and this was just to see what it did with fresh oil. A test start still shows oil pressure warning.

Any ideas? Oil pump? Oil pump chain? I haven't read anything related to oil pump failures, but with ice in the oil sump maybe something broke when I started it.

[Iron Man]

Originally Posted by Atoz

I have a 2009 128i that I've owned since new with 87K miles that I have never had problems with until I got an MIL for misfires. I replaced the VANOS solenoids (with gaskets) as I've read that they're a common failure and installed new plugs since it's due anyway; The car continued to misfire. I let the car sit for about a week while I researched the issue and didn't want to continue driving it with the MIL on.

One night, I decided to take the car out to keep the battery charged as it was cold that night, the temp read 19 deg F when I got in the car. It started right away and as I was beginning to put it in gear I got a low oil pressure light. I immediately shut the engine down and then restarted and the light came back. I was fairly certain the level was good because I check it regularly, but with no dipstick I couldn't confirm.

I did some research and began thinking that there may be some water in the oil due to condensation since I work on a smoke free campus and we have to drive off property to smoke so there are a LOT of short trips. I decided to leave it alone until the weather got warmer to drain and refill the oil.

Last night it was in the mid fifties so I ran another test start and the light came back. When I drained the oil water came out; about a pint, maybe more, maybe less. It was clear so I don't think it's coolant and when I took my glove off it wasn't slippery like coolant should be, the coolant was full and no oil present - again I was thinking condensation, but that would be a LOT of condensation. The oil drain went right to the top of a 7 Qt. pan, I put 6.5 quarts of Mobil 1 5w20 in it as I already had a case for my other car and this was just to see what it did with fresh oil. A test start still shows oil pressure warning.

Any ideas? Oil pump? Oil pump chain? I haven't read anything related to oil pump failures, but with ice in the oil sump maybe something broke when I started it.

Using too low of viscosity of oil will drop your oil pressure as well. Put the right kind if oil in and then see if the low pressure light still comes on. I would never put 5W-20 in your Bimmer.