Nightmare dealer situation (Updated)

[sapote]

Red oil light went on and the engine died.

When the red light popped up, did you also hear the alarm sound? I wonder what cause the engine shut off -- too much friction or not working VANOS caused the cams moved to max retarded. Anyone know if engine can run with no oil pressure to vanos (or unplug vanos solenoid connector)? I seem to remember engine can run with the connector removed, and if this is true, then why OP's engine shut off?

[GreyM340i]

When the red light popped up, did you also hear the alarm sound? I wonder what cause the engine shut off -- too much friction or not working VANOS caused the cams moved to max retarded. Anyone know if engine can run with no oil pressure to vanos (or unplug vanos solenoid connector)? I seem to remember engine can run with the connector removed, and if this is true, then why OP's engine shut off?

I had my radio on however it wasn't loud so not sure if I heard a alarm. I think I down shifted to get off the expressway exit and then noticed my car turned off. It felt the same as someone stalling a stick car on takeoff. I quickly got on the side to let the cars behind me pass. I then tried to start the car and it hardly ran plus I heard a squeal sound before I quickly shut it off. I don't know what that could of been other than metal on metal contact.

[heinzboehmer]

Anyone know if engine can run with no oil pressure to vanos (or unplug vanos solenoid connector)?

Yes it will run with the connector unplugged. I once forgot to plug it in after timing my engine. Sounded like a cammed LS lol

I then tried to start the car and it hardly ran plus I heard a squeal sound before I quickly shut it off. I don't know what that could of been other than metal on metal contact.

A squeal? Like a slipping belt maybe? I would think the engine would clunk and rattle more than squeal if it was running with no oil.

Regardless, sorry to hear this happened to you. Hopefully the dealer agrees to open up the bottom end without much of a fight and you can drive your car around again.

[maupineda]

Hence what I said at the beginning, you need to negotiate and will very likely be in for unplanned costs, but splitting the cost of a rod bearing job is your best bet to ensure nothing happen and have a maintenance job done as a side benefit

this is not about right wrong, but what you can do to make it better for yourself. Ideally non of this should have happened, but it did.

[GreyM340i]

Hence what I said at the beginning, you need to negotiate and will very likely be in for unplanned costs, but splitting the cost of a rod bearing job is your best bet to ensure nothing happen and have a maintenance job done as a side benefit

this is not about right wrong, but what you can do to make it better for yourself. Ideally non of this should have happened, but it did.

I agree about the rod bearings however when I spoke to a local I independent shop he mentioned he would be more worried about the top half of the motor as that area is first to loose oil. He said most likely the bottom half is probably ok because there was still oil in that area. He said he would first check Vanos and the head then move to the bottom half. Said maybe nothing went wrong however no one would know unless both the top and bottom were really checked.

[/M3]

When the red light popped up, did you also hear the alarm sound? I wonder what cause the engine shut off -- too much friction or not working VANOS caused the cams moved to max retarded. Anyone know if engine can run with no oil pressure to vanos (or unplug vanos solenoid connector)? I seem to remember engine can run with the connector removed, and if this is true, then why OP's engine shut off?

The thermal oil level sensor noticed there was too less of an oil and sent a signal to the DME, which immediately destroyed the fuse therefore the engine was no longer running with no oil.

[sapote]

The thermal oil level sensor noticed there was too less of an oil and sent a signal to the DME, which immediately destroyed the fuse therefore the engine was no longer running with no oil.

Do you have any references for this?

[sapote]

I then tried to start the car and it hardly ran plus I heard a squeal sound before I quickly shut it off.
....
when I spoke to a local I independent shop he mentioned he would be more worried about the top half of the motor as that area is first to loose oil. He said most likely the bottom half is probably ok because there was still oil in that area. He said he would first check Vanos and the head then move to the bottom half..

Yes and no.
Crank and rod bearings have more oil than cam bearings, but remember the crank and rods carry more load, and so need higher oil pressure to avoid damaged. I would not worry about the vanos as it carries little load. Yes, I agree that the cams bearings and rockers/lobes should be checked as they are the first to suffer when running with low oil.

The squeal noise is a serious concern, or it could be just the sound of a humpback whale exhaled the air -- the oil pump sucked in air and those pressurized air bubbles escaped the tight bearings making the trumpet noise like a whale.

[GreyM340i]

Yes and no.
Crank and rod bearings have more oil than cam bearings, but remember the crank and rods carry more load, and so need higher oil pressure to avoid damaged. I would worry about the vanos as it carries little load. Yes, I agree that the cams bearings and rockers/lobes should be checked as they are the first to suffer when running with low oil.

The squeal noise is a serious concern, or it could the sound of a humpback whale exhaled the air -- the oil pump sucked in air and those pressurized air bubbles escaped the tight bearings making the trumpet noise like a whale.

This is the problem as I’m not a mechanic or familiar with this motor. So not sure what that noise was however it didn’t sound good to me. Still waiting to hear back from the GM on what they can offer to do. At this point the service department doesn’t even want to look into the motor as they think it’s all fine. He keeps saying that it’s a 95k mile motor that who knows what wear it already had. I told him I understand however the service history I have for it plus I wasn’t the one who made it loose all its oil on the side of the road. This sucks and I’m tired of dealing with it.

[GreyM340i]

The thermal oil level sensor noticed there was too less of an oil and sent a signal to the DME, which immediately destroyed the fuse therefore the engine was no longer running with no oil.

The dealer said it has a safety system that will turn the car off if oil gets too low. Then the independent BMW shop said there is no such thing and they’re lying to me. Not sure who to believe.

[oceansize]

Fuse 30 is what I've seen referenced as being blown by the oil level sensor. However, it will not shut the car off, only prevent it from starting.

Your dealer is lying or ignorant.

[GreyM340i]

Fuse 30 is what I've seen referenced as being blown by the oil level sensor. However, it will not shut the car off, only prevent it from starting.

Your dealer is lying or ignorant.

Yeah that makes more sense. Just not sure what turned the car off while getting onto the exit ramp. That’s my concern.

[heinzboehmer]

Wall of text/pics warning, but I'm pretty sure the signals from the oil level and pressure sensors do not influence engine running or starting.

Here's what TIS has to say about the oil light:



Notice there's no mention of switching the engine off when the oil level is too low.

Fuse 30 is what I've seen referenced as being blown by the oil level sensor. However, it will not shut the car off, only prevent it from starting.

Maybe some people have had it blow when their oil level is low, but I highly doubt the DME is purposefully blowing it. That fuse provides +12V to a bunch of engine components, including the oil level sensor.

The oil level sensor works by heating up a resistive element and measuring how fast it is cooled (by the oil). I suspect what is happening is that the lack of oil does not allow it to cool and the sensor ends up drawing enough current to blow the fuse.


In case anyone wants to read up on this/look at the wiring diagrams/show this to the dealer, the info can be found in the "BMW E46 M3 Coupe / Wiring Diagrams and Functional Description / Body / Displays and information / Warning and indicator lights" section of TIS.

[fattycharged]

The dealer said it has a safety system that will turn the car off if oil gets too low. Then the independent BMW shop said there is no such thing and they’re lying to me. Not sure who to believe.

In this scenario, the indy. They're either lying to you, or they're ignorant, neither is beneficial for your situation.

[Slideways]

heinzboehmer My guess is the engine shut off due to the oil pressure drop resulting in the VANOS system fixing the timing in a position where the engine could not continue running properly.