81EA81 Posted July 17, 2011 Share Posted July 17, 2011 So on I let my mom borrow the BRAT:eek: while I was messing with this sad Geo Tracker that I found,which is a pain in the A to work on compared to a Soob. When she returned she said she noticed the oil pressure had droped to ZERO. She immediately stopped the engine and waited a few minutes for any oil to settle, checked it and there was oil on the dipstick. then she drove it easy the next 6 miles home.The first thing I did was crawl under it to look for the sending unit wire and it was there and intact from what I could tell from the dusk light. I waited for the engine to cool, checked the oil which was at its appropriate level nice and clean and did not smell burnt. when the key is on the pressure gauge jumps to 75, as soon as the engine fires it SLOWLY drops to ZERO. it once hovered around 20 psi once, yes i tried the search feature and couldn't find what I sought. I've heard these can be fairly inaccurate but have little personal experience in this department. Now that it is light out I will go and have a look. Oh yea its a 1986 Subaru Brat with the original EA81 with 168,xxx mi Thank you Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 17, 2011 Share Posted July 17, 2011 You have a wireing problem. GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 19, 2011 Author Share Posted July 19, 2011 So would it most likely be at the sending unit, the gauge its self or the wiring in between? I cleaned the connection at the S U and the little connector about 3 inches after that. I traced the wiring up to the intake where it gose into a harness then up under the coil. Its a yellow wire with a single black stripe. Dose anybody have a wiring diagram? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 19, 2011 Share Posted July 19, 2011 There is a short somewhere in the circuit - when the gauge jumps to 75 it means the lead from the sending unit is grounded. I would disconnect the sending unit and see if it still jumps to 75 with the key on..... could be a short internally in the sender though I've never seen one act that way. GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 19, 2011 Author Share Posted July 19, 2011 So I get nothing with the sending unit wire unplugged key on, I plugged it back in and turn the key to acc. and on and nothing, then I turned the key to lock then back to acc. then it jumped to 75 so that means its getting 12 volts from somewhere its not supposed to? With the key in the "ON" position with the warning lights on, the gauge gets no power. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 19, 2011 Share Posted July 19, 2011 You will have to check the wire for voltage under those various circumstances - unplug the sending unit and check for power to that wire with a multi-meter, etc. GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 20, 2011 Author Share Posted July 20, 2011 At the time being all I have is a test light, Ill update when I have the proper tools. Thanks GD Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 20, 2011 Share Posted July 20, 2011 Test light will work but it's not ideal for this kind of a problem since you can't accurately test the resistance of the sending unit. GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 20, 2011 Author Share Posted July 20, 2011 Ohms is resistance,Right? what should it read,should it have 12.6 volts to it? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 20, 2011 Share Posted July 20, 2011 Yeah - Ohms is resistance. I would have to look at my FSM to know what the resistance should be but it's going to depend on oil pressure which will depend on temperature and engine speed..... GD Quote Link to comment Share on other sites More sharing options...
bheinen74 Posted July 20, 2011 Share Posted July 20, 2011 (edited) possible wrong oil pressure switch? they did make 2 styles...one with light.....one with guage..... Edited July 20, 2011 by bheinen74 Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 21, 2011 Author Share Posted July 21, 2011 I just picked up a cheapy DMM. its a Gardner Bender GDT-311. Dose AC/DC volts and OHMS. I drove the BRAT once about 3 miles and the pressure gauge worked upon start up. about a minute later it went out. I somewhat rely on this gauge when I drive so im not comfortable driving it untill i get this sorted. anybody know of any common places to check for shorts, possibly where wires can rub together? I know its not a huge problem,but any input will help. thanks Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 21, 2011 Share Posted July 21, 2011 Check the resistance of the sending unit both when it's at rest and when the engine is started and running. Watch what the resistance does - it should start out higher, and drop as the engine starts and the oil pressure rises, etc. GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 24, 2011 Author Share Posted July 24, 2011 Ive been driving the Brat very little lately since the oil pressure gauge, and its been bumming me out. that car is what motivates me to get up every day. well on my way home last night my bright lights just went out on me right as i was pulling into my driveway,still had low beams to park. today I drove it a bit to try n cheer me up(Brumby rumble). and I noticed that when I flash the brights the voltage gauge drops to zero, it returned as soon as the switch did. sometimes it would do this and other times not. I made it home ok with the oil pressure gauge temporarily working. Then just about ten minutes ago I fired her up just to here the sweet sounds and I flashed the brights to see if they'd work, first try all was good Second try out went the lights,then I noticed a little puff of smoke rise up from the steering collum with the unmistakable smell of burnt wire:eek: I instantly shut down the car, popped the hood and dropped the ground wire off the batt. as fast as I could. Now im very worried the Brat will be decommissioned, I hope all will be ok if you have any ideas what could be causing this wiring problem please speak up, anything helps. keep in mind I treat this car better then my nuts, no offroading or anything more then road crusing Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 24, 2011 Share Posted July 24, 2011 I think you need to seek some professional assistance with your electrical issue. It sounds as if your wireing is dangerously close to melting either due to high resistance at a connector or because of improperly fused aftermarket wireing..... there's just no way to tell without being there. Your symptoms are not typical. There are board members in your area - reach out and possibly someone can take a look at it that knows their way around a DMM. GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 24, 2011 Author Share Posted July 24, 2011 Thats bad news, Im pretty well broke. It should all be original wiring, im the third owner. I got it from a guy who had it since 1991.he seemed to maintain it ok. it came with a haynes manual that had every other page book marked. the only thing aftermarket is the stereo which had to of been installed in the mid 90's Well, wish me luck:-\ Quote Link to comment Share on other sites More sharing options...
Mykeys Toy Posted July 24, 2011 Share Posted July 24, 2011 As GD said their are board members in your area and most of them will take the time to help you if they have it to give. A shop would be best but if not start calling some most if they are reputable will try to walk you through the troubleshooting process because it reflects well on their business (word of mouth rules ). Personally I would start carefully disassembling things around the column until you have located there the smoke came from more often than not the part that burnt if not exposed wire, will lead you to the problem. Check your fuse box and surrounding wires for fuses that have been bypassed or tapped for other purposes. If nothing check wires that have any place at all to rub on anything. Also check your fuseable links. Then if you are still not resolved check the grounds around the battery and have your alt checked out at the local APS. I am by no means a good DIY'er but this is how I would start. keep track of all the symptoms they may spark a memory from another someone here that may lead directly to the problem. If something can happen chances are someone here has had to deal with it. Mike Quote Link to comment Share on other sites More sharing options...
NWSubie Posted July 24, 2011 Share Posted July 24, 2011 Sorry to hear of your luck I hope you can find the gremlin soon so you can get to cruising again. My 80 wagon has had many electrical problems since I bought it. Such as its headlights just shut off, I thought it was a fuse but it was not so in the end I had to run a whole new power wire to a new (ATC) fuse box then to the switch. I now have my stereo and Head lights running off new wiring. I just think that the wires are just getting old because I have found quite a lot of wires that when I went to replace the stock connecters had several inches of green corrosion going up the wire. (on the inside) I assume that cant be good for things to operate. Also check your grounds a bad ground can make some odd things happen. Good Luck Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 26, 2011 Author Share Posted July 26, 2011 here is a quick video, I hope its not me being stupid. http://www.flickr.com/photos/59058330@N03/5976462598/ Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 26, 2011 Author Share Posted July 26, 2011 Is there to much power going to the switch,or did i overload it? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 26, 2011 Share Posted July 26, 2011 Looks like you probably have a short to ground somewhere...... the weird part is that the high beam switch *should* be grounding the high beam bulbs - which should provide enough resistance to keep a direct short from occuring. You don't have anything strange going on with your inner headlight (the high's) wireing do you? GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted July 26, 2011 Author Share Posted July 26, 2011 (edited) Im in the process of tracing the wires, ill update when i find anything unusual. I might have to change the thread name while im at it Dose anybody know if the Opsi G and the high beam switch would be tied together? Or are they shorting each other out? Edited July 26, 2011 by 81EA81 Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 26, 2011 Share Posted July 26, 2011 They should not be associated in the harness, no. GD Quote Link to comment Share on other sites More sharing options...
81EA81 Posted August 1, 2011 Author Share Posted August 1, 2011 Ive tried looking at wiring diagrams in a Haynes manual and I cant make much sense of it.What colored wire where?What grounds are for what?After jiggling some wires around I got the oil pressure gauge to work,(for now) but my highbeams are still ************ing with me. I have a spare steering colum with the blinker/headlight switch I had though about just swaping out with the old one. Then I thought, If the current one is frying, whats to stop the second one from doing the same? I think I could unplug it and check between the connections for volts/resistance but I dont know what it should be. I checked all fuses and I have power to all.I found a few plugs near the fuse box going to nothing. I also saw a Green connector going into a blue connector, It dosent look right to me but I didnt mess with it because I dont know what its for. theres also the female end of one of theses near the power cable coming from the stereo. its a light green wire with a red stripe Circled here http://www.flickr.com/photos/59058330@N03/5999073272/ Some Blue on Green action http://www.flickr.com/photos/59058330@N03/5999073192/ Any Knowledge or Ideas? or grounds to check? Thanks Quote Link to comment Share on other sites More sharing options...
81EA81 Posted August 2, 2011 Author Share Posted August 2, 2011 Dose anybody know if it is safe to run around with the steering colum unplugged? Id have no blinkers, but hey? what to do? I need some wheels with MPGS Quote Link to comment Share on other sites More sharing options...
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