Oil gauge and others not working right (Stock gauges)

[bmwracing_6]

Ok when I have the car off the oil pressure gauge (on the dash) is at 0 when and when I turn the key on then it goes to the max. What can cause this? How do i fix it? Its not the gauge cause i have used 2 different gauge clusters in it and both do the same thing. I also am having a problem with my Tach is it not working at all but my other cluster does work. But i have 2 cars and they both need one so I was wondering if it is possible to fix the tach or replace it without getting a whole new cluster. I really dont want to buy a big tach to put on the dash so i was wondering if this is possible thanks.

 

[luv2rallye]

Your oil pressure sending unit is shorted or the wire to it is shorted to ground. Disconnect it to see which. It's the big one near the oil filter. If neither tach works in the one car try swapping power transistors to see if it's the problem.

 

[bmwracing_6]

The original tach does not work and i switched it with the other one and it does work on it but my question is can it be fixed and how? Thanks

P.S I looked at the sending unit wire and it is barely hanging by one strand of wire i am going to replace the wire and see what happens

Thanks Justin

 

[bmwracing_6]

I fixed the wire and it still does the same thing. Could the sending unit be be bad? It is also idling at 3000 rpms. And I am getting alot of vacuum and no boost this is a different problem but still needs attention. Just for reference this is a JDM swap I am doing. Thanks Justin

 

[luv2rallye]

Unhook the sender. If it still goes to max when key is on, then the sender is not the problem (you have a wire short). If not, replace the sender.

 

[bmwracing_6]

Ok I got it... it was the sender but I have never had this car running right yet so I don't know where the oil gauge is suppose to sit at in idle it sits right in the middle is this right?

Thanks, Justin

 

[luv2rallye]

They usually read very low at idle (barely above 0 but definiately above it - maybe 1/8).

 

[bmwracing_6]

well i have no idea it sits in the middle at idle and it does not go up when i rev it.

 

[selmerguy]

well i have no idea it sits in the middle at idle and it does not go up when i rev it.

When the car warms up and the oil looses some of its viscosity the pressure will drop some at idle. If your idoit light comes on you have a problem if not you are good to go.

 

[bmwracing_6]

ok thanks i will have to check to see if it goes down after warm up.