Oil pressure light?

[E30ruben]

Okay so I swapped out my low compression 318i motor with another one I bought used, everything is fine but 2 things: my temp gauge isn't working and my oil pressure light is on but not fully lit.. For the temp gauge I tried switching sensors off my old motor and still doesn't work, any suggestions for both problems please? Thanks guys!

[jaywood]

My oil pressure light likes to flicker. I do not know why. Is yours flickering, or just really dim?

[flyboyx]

well, here is something to give you pause: assuming the oil pressure light is functioning properly, it only lights up when your oil pressure is really really low. somewhere in the line of 5 to 7 psi. check your grounds on the engine. there should be a really big wire from the motor mount arm to the chassis. make sure that is hooked up well and the connections are clean.

when you turn on the key before starting the engine, does the oil pressure light light up brightly?

you will definitely want to get this one figured out before you drive the car for any length of time.

you did pull off the oil pan and take a main bearing off to take a look at the shells while you had the engine out right?

could be a bad sensor i guess. you could try taking the sending unit off your old engine and swapping them out.

[E30ruben]

Will defeninately be checking out if the light turns bright before turning the car on, also, my ground wires. Worse come to worse ill swap sensors and oil pump off of my old motor, thank you!

But what about that temp gauge? :/

[flyboyx]

well, that is less of an issue compared to oil press. fix the ground first and see what becomes of it. trouble shoot it the same way. if your oil press is really that low, you need to check the bearings/clearances with some plasti gauge. could be the oil pump but likely you have worn out bearings or a bad sensor. if you pull the pan check the main bearings first. if they are good, go from there. if you unbolt the rods, you need to replace the cap screws.

[E30ruben]

Sooo I've fixed everything car runs great BUT When my motor warns up to normal operating temp my oil pressure light comes on and stays on. Should I go thicker oil? New oil pump..?

[vpilarrt]

This an M42 or M10 engine? I accidentally switched the oil pressure and temp plugs once on my M42 and got the scenario you're describing. Its easy to do because they close to each other and both plugs fit either sensor.

[ELVA164]

Sooo I've fixed everything car runs great BUT When my motor warns up to normal operating temp my oil pressure light comes on and stays on. Should I go thicker oil? New oil pump..?

What do you mean by "fixed everything?" What did you find out/replace?

[E30ruben]

Lol @vpilarrt that was the situation, except the guy that swapped my motor did that lol but after I switched the plugs back the car runs fine, no check engine light. But the oil pressure light turns on when it warms up.