Manxter Posted September 5, 2010 Share Posted September 5, 2010 I'm new to water cooled EFI motors (always had sand rails with VW motors) so I'm no expert but I've had a problem I can't figure out. I recently (June) had my 2.5 Liter turbo (9 lbs boost) engine rebuilt by Outfront after it blew up. The motor is in a MGM/FRP Manx. It's a long travel off-road car built on a VW pan with a VW 091 trans. It's been running fine since then untill today..... I started out on a pretty whooped out trail and bottomed out a few times in g-outs. Then was cruising down a dirt road and realized I missed a turn. I hit the brakes pretty hard and decelerated pretty quick and the car stalled. This has happened before but it always restarts. Not this time. I tried to start it. It started but idled very rough at about 700 RPMs. Then I looked at the oil pressure and it was 0. I turned the car off and back on. The oil pressure needle never moved. I checked the oil and it looked good. Any thoughts? Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted September 6, 2010 Share Posted September 6, 2010 Hello and welcome to the board! That sounds like a nice setup. Question #1 would be the gauge. Is it working properly? If it's an electrical gauge maybe you lost a ground to the engine or something like that and that is also making the engine run poorly now. The oil pump is driven right off the crankshaft, so it's pretty hard for the engine to run without the oil pump operating. I don't think that part of the crank even has a keyway. Maybe the suction strainer fell off or something if the gauge is actually correct and it has enough oil in it. Or maybe the pressure relief valve on the pump opened and for some reason got stuck open. I'm assuming you've got a normal Subaru oiling system, unless you have a dry sump setup or something like that. Quote Link to comment Share on other sites More sharing options...
nipper Posted September 6, 2010 Share Posted September 6, 2010 I'm going with the pickup falling off the pump. Is the oil pan dented? That can cause the issue too. Quote Link to comment Share on other sites More sharing options...
Manxter Posted September 6, 2010 Author Share Posted September 6, 2010 The oil pan is shortened to make more clearance. My rear suspension has been an issue and I've been trying different set ups but the skid plate under the sump takes a beating. I took the skid plate off after my last post. It's not dented but is beat up from rocks getting between the skid plate and the sump. I drained the oil and it turns out I was running a quart low. I put new oil in and it didn't want to start at all now. When I had the engine rebuilt, they put a new oil pick up in cause they said the other one was too short and was probably part of the reason the engine failed last May. Quote Link to comment Share on other sites More sharing options...
Manxter Posted September 6, 2010 Author Share Posted September 6, 2010 Hello and welcome to the board! That sounds like a nice setup. Question #1 would be the gauge. Is it working properly? If it's an electrical gauge maybe you lost a ground to the engine or something like that and that is also making the engine run poorly now. QUOTE] I forgot to mention the guage. The guage doesn't even blink when I turn the key. I can't remember if it cycled before but it's not moving at all now. I'll have to look for the ground. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 6, 2010 Share Posted September 6, 2010 Screw a mechanical guage into the port and see if you have pressure while cranking. GD Quote Link to comment Share on other sites More sharing options...
Manxter Posted September 6, 2010 Author Share Posted September 6, 2010 I found that the wire going to the oil press guage was fractured at the connector on the motor. I replaced the connector and the guage is working. I do have pressure while the motor tried to turn over. But.... it still won't turn over. Then while I was looking around there, I found another fractured wire. I think it goes into the plug that plugs into the O2 sensor. There are 4 spaces on that plug but only three wires going into it. I'm wondering if the fractured wire I found goes into the 4th spot. Quote Link to comment Share on other sites More sharing options...
Manxter Posted September 6, 2010 Author Share Posted September 6, 2010 I tried to post some pics but when I click the "insert image" icon it asks for a URL address and I cant figure out how to attach pics from my hard drive. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted September 7, 2010 Share Posted September 7, 2010 Hey if you want to upload the pics to http://www.porcupine73.com/upload I can make them show up in the thread. Or if you click 'manage attachments' when posting (you have to be in the 'advanced' view) then you cna upload them there too. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted September 7, 2010 Share Posted September 7, 2010 I tried to post some pics but when I click the "insert image" icon it asks for a URL address and I cant figure out how to attach pics from my hard drive. That uses a url from an image host site such as photobucket. You upload the pics there and copy paste the link here. Or you can use the attachments link to upload pics directly to this site and they will show as thumbnails at the bottom of your post. Glad you found your no pressure bug. The no start, first things first. Do you have spark? Do you have fuel? Quote Link to comment Share on other sites More sharing options...
Manxter Posted September 7, 2010 Author Share Posted September 7, 2010 That uses a url from an image host site such as photobucket. You upload the pics there and copy paste the link here. Or you can use the attachments link to upload pics directly to this site and they will show as thumbnails at the bottom of your post. Glad you found your no pressure bug. The no start, first things first. Do you have spark? Do you have fuel? I'll work on the attachements tonight. Yeah, the car wants to start. And if I give it some gas, it will run with the RPMs up but stalls at idle. I'm going to try to find a manual for the motor on line. The mystery wire is black with a yellow stripe and orange dots. There is an open slot in the plug that goes into the black box but I'm not sure the wire went there. My neigbor who is a mechanic says the black box is a Throttle Position Sensor, not the O2 sensor. Quote Link to comment Share on other sites More sharing options...
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