TheSubaruJunkie Posted March 2, 2008 Share Posted March 2, 2008 So everything is connected, bolted together, fluids where they should be. Go to start the car and it turns over, i have no spark I checked, rechecked and checked again. All the wiring i can clearly see is reconnected. What could cause the coil pack not to send spark? -Brian Link to comment Share on other sites More sharing options...
subaru360 Posted March 2, 2008 Share Posted March 2, 2008 So everything is connected, bolted together, fluids where they should be. Go to start the car and it turns over, i have no spark I checked, rechecked and checked again. All the wiring i can clearly see is reconnected. What could cause the coil pack not to send spark? -Brian No signal from the crank or cam sensor, bad ignitor or something not plugged in you might have missed? Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 3, 2008 Author Share Posted March 3, 2008 checked, checked, checked. How do I tell if there is no signal comming from the cam or crank sensor? I have all wiring connected. Link to comment Share on other sites More sharing options...
subaru360 Posted March 3, 2008 Share Posted March 3, 2008 To start with, does the tach go up when you crank it? That's a good first step. If you have a scan tool that can display sensor values that is an easy way to check. Or connect a voltmeter to the 2 wires off the sensors, set it to AC volts and see if it reads anything. Do you have fuel pressure and injector pulse? Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 3, 2008 Author Share Posted March 3, 2008 No real way to check for fuel pressure. I first checked for spark, and after finding none I decided to figure this out before I start to chase down a fuel problem. When cranking over the motor, the tach does not budge. CEL does come on with the key. So i guess the ECU is getting the power it needs. Im checking the .pdf version of the service manual, and the wiring diagram isnt much help to me. I do know, there were 3 plugs on the backside of the motor, center near the throttle body. two were 3 spade plugs, one was a single spade plug. When removing the motor, i failed to disconnect these 3, and I ended up ruining them. One of the 3 spade connecters just broke the locking tab. I now have it secured with a zip tie. The single spade connector tore from the wire, so I used a standard butt end connector and just reconnected them. The third 3 spade connector was completely destroyed. the 3 wires comming from the harness side were exposed. I matched the colors and right now they are just connected to the pins in the engine side until I can find a better replacement. Im thinking these are the cam angle and crank sensors?? Link to comment Share on other sites More sharing options...
subaru360 Posted March 3, 2008 Share Posted March 3, 2008 Looking at that wiring, I think that is where your problem is. Off the top of my head, I think the broken conneector is the crank sensor and the other is several other engine sensors. You should fix that right and go from there. After the wiring repairs, check for continiuty with an ohm meter. It almost looks like you have the pins touching and shorted. Link to comment Share on other sites More sharing options...
Sonicfrog Posted March 3, 2008 Share Posted March 3, 2008 No signal from the crank or cam sensor, bad ignitor or something not plugged in you might have missed? Ditto. Link to comment Share on other sites More sharing options...
ShawnW Posted March 3, 2008 Share Posted March 3, 2008 Its also entirely possible you have wire shielding touching actual internal wire. Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 3, 2008 Author Share Posted March 3, 2008 Shawn what do you mean by that? Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 3, 2008 Author Share Posted March 3, 2008 I have the car wired for VRG's laptop scan tool... and i have an old laptop that is setup with only the scan tool on it. I dusted it off, and hooked it up. The scan tool recognized engine RPM when cranking the engine over. I dont have a multimeter at home, so this was just a quick test to see if the ECU is seeing any RPM, which indicates it does. I was swapping the 3 loose wires around on the connector in every combination I could. A couple combinations the tach would just sit there and a couple the tach would kinda bounce when turning the engine over. I'd like to check the ECU for errors, but i have a raging headache now, and i think im going to toss the towel in for the night. Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 4, 2008 Author Share Posted March 4, 2008 Ok so im at work talking to one of the mechanics I work with. He's gone thru training for auto's even tho we work on construction equipment... etc... Anyhow, he was telling me that a car is able to run on only the crank sensor, and even if the cam sensor was disconnected the motor should still run, but would run like ************. From what he was saying, is vehicles are programmed to use the crank sensor for spark, and the cam sensor for timing. Mind you, he's never touched a subaru, so I can't put much truth to all this, but he has gone through more training than I so I cant call him a liar. Is there any truth to this? Link to comment Share on other sites More sharing options...
tcspeer Posted March 5, 2008 Share Posted March 5, 2008 Is the connector plugged into the coil pack? I know it's a simple suggestion but I have not seen it mentioned. That small plug can hide very easy. Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 5, 2008 Author Share Posted March 5, 2008 checked that time and time again. Wish it were only that simple. Link to comment Share on other sites More sharing options...
Durania Posted March 5, 2008 Share Posted March 5, 2008 Maybe have someone wiggle the crank sensor wire while turning motor over. Link to comment Share on other sites More sharing options...
Hondasucks Posted March 5, 2008 Share Posted March 5, 2008 The single connector wire is the knock sensor, the other two are your cam and crank sensors. I don't know exactly which is which, but BOTH of them were hashed on my 91 turbo legacy, had to trace the wiring back to the ECU with my DVOM to figure out which one was which. I have the diagram around here somewhere from the FSM, but it sounds to me like you have one as well. I had to go to the junkyard and cut the connector off a car in the yard and splice them in. The single pin connector for the knock sensor is a sheilded cable on one end, make sure you don't tie the center wire (signal) to the outer shield, or the ECU won't get a signal from the knock sensor, and it will throw a code and it'll run a retarded timing map. Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 5, 2008 Author Share Posted March 5, 2008 I just went and pulled codes from the ECU, and i get code 11: CODE 11:No signal entered from crank angle sensor, but signal (corresponding to at least one rotation of the crank) entered from cam angle sensor I trace the wiring from that damaged connector and it does lead to the crank sensor. Guess I gotta find a connector at the yard and splice it in. Then try. And yes Andrew, i got a .pdf of the FSM Link to comment Share on other sites More sharing options...
frag Posted March 5, 2008 Share Posted March 5, 2008 About the cam position sensor. I forgot to reconnect it the first time I replaced the timing belt and the car would not start. Just to confirm that if something's wrong with this sensor, the car might not be able to start. HTH. Link to comment Share on other sites More sharing options...
Hondasucks Posted March 5, 2008 Share Posted March 5, 2008 I just went and pulled codes from the ECU, and i get code 11: I trace the wiring from that damaged connector and it does lead to the crank sensor. Guess I gotta find a connector at the yard and splice it in. Then try. And yes Andrew, i got a .pdf of the FSM That was my guess, since most 4 cylinder cars can run with a signal from the crank sensor and not the cam, since there are only two possibilities of what cylinder #1 is doing when the crank sensor sees TDC, top of compression or top of exhaust, but not with the cam and no crank, since the cam sensor usually just shows TDC of the compression stroke of the #1 cylinder, and the ECU won't know anything else besides that so it won't know when to fire anything else which is why your car won't start, the ECU has no idea what angle the crank is at, so it has no clue when to fire the spark. Link to comment Share on other sites More sharing options...
Cougar Posted March 6, 2008 Share Posted March 6, 2008 Have you checked the tabs on the crank sensor to make sure none have been broken off? This has happened to some folks with this kind of problem. Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted March 6, 2008 Author Share Posted March 6, 2008 I have not pulled the crank sensor to inspect it. I don't remember touching it when I had the motor apart either. Was only working in that area while installing new t-belts. Link to comment Share on other sites More sharing options...
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