M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Engine + Driveline => Topic started by: carlos318is on March 29, 2011, 01:23:17 PM

Title: Need your help again
Post by: carlos318is on March 29, 2011, 01:23:17 PM

I am going to wire up a a set of VDO gauges what I need to is how do you wire up a OIL pressure gauge to a E30 318is M42

Thanks guys :D

Title: Need your help again
Post by: DesktopDave on March 29, 2011, 03:39:58 PM

I'd either pull the plug off the current oil pressure sensor & hook it up to a gauge, or use that place for the aftermarket sender.  Maybe even tee it off & use both?

Title: Need your help again
Post by: carlos318is on March 29, 2011, 06:00:55 PM

Where is the oil pressure sensor on the engine

Title: Need your help again
Post by: DesktopDave on March 29, 2011, 07:37:19 PM

It's threaded into the rear side of the oil filter housing, near the middle, under the intake manifold.   Small brass hex sensor with a two prong plug.  You can see it here in the left center of the pic.

(http://i729.photobucket.com/albums/ww299/desktopdave/318i/th_IMG_1463.jpg) (http://s729.photobucket.com/albums/ww299/desktopdave/318i/?action=view¤t=IMG_1463.jpg)

Title: Need your help again
Post by: Ryann on March 29, 2011, 09:37:30 PM

Assuming your gauge is electrical and not mechanical and also that the oil pressure gauge didn't come with it's own sender, you're going to have to find a compatible sender for that gauge and then find a place in the oil galley to thread it into (maybe someone can chime in here, idk). I believe the e30 m42 has an oil pressure SWITCH which simply causes the instrument panel oil light to come on in the absence of oil pressure and will not work with your gauge. VDO should have available a sending unit with the proper Ohms range for that gauge.

Dave's right, you may have to acquire a T fitting so that the VDO sender and factory switch use the same port on the oil filter housing. Or you could pull the "OIL" bulb in your instrument panel and toss the switch, using that port for the new sender exclusively.

Title: Need your help again
Post by: colin86325 on March 30, 2011, 01:16:17 PM

Remote mount the pressure sensor to the body. I had one mounted right to the stock location and it vibrated to pieces after a few months. The same thing will happen on an S14 engine.

Title: Need your help again
Post by: rob_e30 on March 30, 2011, 05:12:22 PM

The stock sender in these cars is a switch... low/no oil pressure = light on.  Hooking up a gauge to the stock sender won't work.

Most aftermarket gauge senders will not fit in the fitting where the oil pressure switch is.  We had some fittings made up for our own use that allows you to use a standard oil pressure sender (1/8" NPT) and fits in the M12 (I think) threaded socket.  It's the same size as the oil drain plug.

http://www.hqautosport.com/products2.html

In addition to the location of the stock oil pressure switch on the back of the oil filter housing, there is a blank threaded bung on the front of the oil filter housing.  You can use an allen head socket to remove the blank and install the sender in that location.  We use both on the race car... the front for oil temp and the rear for pressure.

Title: Need your help again
Post by: Ryann on March 30, 2011, 07:45:33 PM

^Hah! I knew you'd know a second location.:)

Title: Need your help again
Post by: carlos318is on May 07, 2011, 03:42:57 AM

Thanks for your help guys