1991 325i - left turn signal and tail light blinker but does not blinker when select to on and start

Hi, I have a weird electrical problem.
1) key on 'acc' position, head switch at "off"position. When I select left turn, the front & rear left turn signal blinks But the left rear tail lights also blinks ! It does not happen on the right side.
2) key on 'on' or start position, head switch at "off" position, when I select left turn, it does not blink but stays on.
3) Hazard lights works normal Only if the key is in the "acc" position.
4) Rear light, license plate warning light comes on.
5) sometimes "engine oil" light comes on but engine oil level is good.
6) bulbs all changed, flasher relay changed, problem still exists
Has anyone encountered this strange electrical problem on the BMW E30 ?
Anyone has any thoughts on the cause and solution ?
Thanks

Hi Jay,

I can only comment on the engine oil light. I drive the car almost everyday. If I park uphill, the low oil light often persists for a couple days regardless of parking orientation or oil level. If it persists for 5 days, then I check the oil level with the dipstick.

I think my car can be "emotionally needy" at times. I sense that it wants to be fussed over and electrical oddities are its form of expression. It you engine suddenly is demonically possessed, coughing, choking, and misfiring on a misty or humid day, this might be the spark plug wires and distributor cap. I've been there and done that.

Best, Kelly

I can comment on the oil level warning. The sensor is a float with a magnetic switch submerged in the motor oil After many years, the deposits of dirt from the oil cause the float to become sticky and it will not go up and down with the oil level. It is unreliable as a sensor. One could remove it from the engine and try to clean it but it is enclosed in a sleeve with very small openings top and bottom to damp out surges such as might be experienced while cornering.

They are expensive to replace so what I did was to short two of the prongs of the connector so that it always indicated full. I usually check my oil level every time I fill up the gas tank anyway.

The electrical issue with the lights may just be a bad ground connection. Possibly in the taillight assembly. They get corroded due to condensation in the trunk. Try cleaning the connector sockets and blades of the housing. The turn signal may be finding a ground through the tail light.

Bob in Lake Havasu

Quote
Bob in Everett
I can comment on the oil level warning. The sensor is a float with a magnetic switch submerged in the motor oil After many years, the deposits of dirt from the oil cause the float to become sticky and it will not go up and down with the oil level. It is unreliable as a sensor. One could remove it from the engine and try to clean it but it is enclosed in a sleeve with very small openings top and bottom to damp out surges such as might be experienced while cornering.

They are expensive to replace so what I did was to short two of the prongs of the connector so that it always indicated full. I usually check my oil level every time I fill up the gas tank anyway.

The electrical issue with the lights may just be a bad ground connection. Possibly in the taillight assembly. They get corroded due to condensation in the trunk. Try cleaning the connector sockets and blades of the housing. The turn signal may be finding a ground through the tail light.

Yes, bad ground can do that and cause all kind of strange things. Renew the taillight ground, if you find it corroded.