I changed my oil pump and oil pressure sensor... why Is my oil light still on? is it a code that I need to erase? plz help... got a long trip ahead of me... dont want to blow the engine....

 

Pull out the sensor and install an oil pressure gage. See what the pressure is and go from there. Usual readings are 10psi per 1000 rpm. It should idle around 10psi. If lower then that then you have some bearing problems. The oil light usually comes on under 5-8psi.

 

silly question perhaps, but what grade oil do you have in hte engine? should be 10W30 for most all conditions, except perhaps for summer duty in a desert climate, then perhaps 15w40

 

gonna change my oil to 15w40 tomorrow when I get out of work....hopefully this turns off the light....is their an additive that I can buy to clean out my oil passages? gonna get the pressure guage as well... the car has had this light on since I bought it 2 years ago so I dont know...wouldnt it have messed up sumthing by now????

 

I wouldn't use 15W40 unless your temps are /always/ in the 70F+ (20C+) range.

fwiw, clogged oil passages would probably make your oil pressure HIGHER rather than lower. assuming the sensor is working properly, low oil pressure means your bottom end bearings are very worn and oil is getting past them too easily.

 

What year and model is it? Early 240's are notorious for the oil sender wiring failing where it is routed under the crank pulley. It is also quite fragile in the vicinity of the sender because it and the excitor wire for the alternator get abused when filters are changed. The target for the idiot light sender is 7 p.s.i. to come on. Generally, if the light is on solid and oil pressure truly is super low, there will be noise from the motor (rattle).

 

swift.. theres no rattle....and the wire seems a bit beat... its a 91' 740...regina...8 valve...the engine seems to run smoother with the pump from the other b230....

 

Yeah, first thing to do is confirm op with a mechanical gauge. It may be simply a bad sender and/or wire leading to it. Definitely not something to gamble with. So, apparently you installed a used oil pump? Did you use a new oil delivery seal? Those seals can and do fail, causing low op.

 

With my new 940 i got i had the same problem. Turns out it was bad soldier joints behind the cluster.

I added fresh soldier and VIOLA! fixed.

 

I prefer the cello...but I do love me some viola from time to time...