root4u Posted February 5, 2008 Share Posted February 5, 2008 Help - My 92 legacy has an intermittent starting problem. The engine cranks, sometimes starts and other times wont. Once it starts, it runs fine. I have checked/ replaced a number of components including: wires, plugs, fuel filter, coil, cam sensor, crank sensor, battery, starter and fuel pressure regulator. None of them were obviously broken and the problem is not resolved. The check engine light is not on. Fuel pressure tests okay. Fuel pump turns on when ignition goes on. Have taken it to a Subaru mechanic and local mechanic and it started fine for them! Now it wont start in my garage and I'm out of ideas. Any suggestions on things to check? Thanks! Quote Link to comment Share on other sites More sharing options...
nipper Posted February 5, 2008 Share Posted February 5, 2008 When it won't start, is it dead for a period of time, and then it starts? Or wont it start on the first attempt, then fire off on the second attempt? nipper Quote Link to comment Share on other sites More sharing options...
root4u Posted February 5, 2008 Author Share Posted February 5, 2008 The times it wont start, I can try a number of times without success, until the battery's flat. Ocassionally I have pumped the accelerator and it's caught but generally not. Then I try the next day and it starts straight up. When it won't start, is it dead for a period of time, and then it starts? Or wont it start on the first attempt, then fire off on the second attempt? nipper Quote Link to comment Share on other sites More sharing options...
EVOthis Posted February 5, 2008 Share Posted February 5, 2008 igniter?..... Quote Link to comment Share on other sites More sharing options...
screwbaru2 Posted February 5, 2008 Share Posted February 5, 2008 "Ocassionally I have pumped the accelerator and it's caught but generally not. Then I try the next day and it starts straight up". I'm thinking fuel pressure loss with the engine off. The pressure is leaking down and takes some time to built back up. Tee in a pressure gauge to the fuel line, run it, shut it off and let it sit, overnight. It should hold the pressure. If not you gota find the leak. Make sure 1st the gauge setup isn't leaking. Sometimes the injectors leak down. Quote Link to comment Share on other sites More sharing options...
nipper Posted February 5, 2008 Share Posted February 5, 2008 "Ocassionally I have pumped the accelerator and it's caught but generally not. Then I try the next day and it starts straight up". I'm thinking fuel pressure loss with the engine off. The pressure is leaking down and takes some time to built back up. Tee in a pressure gauge to the fuel line, run it, shut it off and let it sit, overnight. It should hold the pressure. If not you gota find the leak. Make sure 1st the gauge setup isn't leaking. Sometimes the injectors leak down. I'm thinking its flooding from a leakdown too. This can also cut down the oils life. Does your engine oil smell like gas? nipper Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted February 5, 2008 Share Posted February 5, 2008 How about engine coolant temp sensor? Quote Link to comment Share on other sites More sharing options...
nipper Posted February 5, 2008 Share Posted February 5, 2008 It's the only thing he hasnt replaced yet, mights as well. nipper Quote Link to comment Share on other sites More sharing options...
OB99W Posted February 5, 2008 Share Posted February 5, 2008 [...]Ocassionally I have pumped the accelerator and it's caught but generally not.[...]Here's something you can try next time...Instead of pumping the accelerator, hold it down to the floor while cranking. That should help "unload" any excess gas, if it's the problem. The engine might then start more readily, and if so be a clue that one or more injectors are leaking down and causing flooding. The opposite problem would be if the injectors aren't being told to open at all. Noid lights could be used to check for injector pulses. Assuming that air and compression aren't intermittent, if fuel isn't the problem, that leaves ignition. Can you check for spark? Or, as has been suggested, consider the CTS. Quote Link to comment Share on other sites More sharing options...
tcspeer Posted February 6, 2008 Share Posted February 6, 2008 Take the big hose off of the I.A.C. valve and spray some injector cleaner into it, this might help. Quote Link to comment Share on other sites More sharing options...
njdrsubaru Posted February 6, 2008 Share Posted February 6, 2008 fuel pressure regulator... was replaced, but that really sounds like it is a fuel presure regulator problem, then again may be loosing pressure somewhere Quote Link to comment Share on other sites More sharing options...
root4u Posted February 7, 2008 Author Share Posted February 7, 2008 Thanks for all the suggestions but still no start! I changed the fuel injectors, the mesh portions of the old ones looked dirty but it still didn't start. Then I noticed something strange. When I first turn on the ignition (ie first two seconds when the fuel pump kicks in) or whenever after the ignition is on and I press on the throttle, there's a "arrrrr" sound - something like a dud relay coming from the transmission! I can stop this noise by disonnecting one of the two large electrical harnesses to the transmission or the throtle position sensor. So I swapped the tps but still no start! I'm not sure why a problem in the tranny would stop it starting but who knows. Does anyone have any other clues? Quote Link to comment Share on other sites More sharing options...
nipper Posted February 7, 2008 Share Posted February 7, 2008 That sound may be the Duty C solenoid, its normal. So its not starting at all now? Do you have spark and can you hear the injectors clicking? Quote Link to comment Share on other sites More sharing options...
root4u Posted February 7, 2008 Author Share Posted February 7, 2008 It's not starting. I tried holding the accelerator down as suggested to resolve the flooding. What's the best way to check for spark? Not sure about the clicking will have to listen tomorrow. That sound may be the Duty C solenoid, its normal. So its not starting at all now? Do you have spark and can you hear the injectors clicking? Quote Link to comment Share on other sites More sharing options...
nipper Posted February 7, 2008 Share Posted February 7, 2008 OK lets do some tests. Get yourself a haynes manual. The cam sensro, the crank sensor, and the collant tepm sensor can all keep the car from starting. I bet the coolant temp sensor is shot. The position sensors put out a low AC signal to the cpu. Hand crank the engine and look for a heartbeat on an analog meter. Cam sensor is spark and fuel, crank is timing (dwell). Next use an ohhm meter to check the CTS to see if it has an open. Also check the connnections to make sure they are clean connections. Checking for spark is easy. Just hold the wire 1/8-1/4 inch away from the engine. You can use an insulated screwdriver in the spark plug boot, or ground out an old spark plug in the boot. you should get a nice strong blue spark. nipper Quote Link to comment Share on other sites More sharing options...
tcspeer Posted February 8, 2008 Share Posted February 8, 2008 For just a few dollars you can get a inline plug tester from the auto store, it has a glass window so you can see the spark its a very handy tool. I take the fuel line off at the filter to see if Iam getting fuel, But you must be careful if you do this, and dont let the fuel and sparks get together. Might be better just to open gas cap and hold ear close while someone turns the key on, if fuel pump is working you will hear it run for just a few seconds. Quote Link to comment Share on other sites More sharing options...
nipper Posted February 8, 2008 Share Posted February 8, 2008 For just a few dollars you can get a inline plug tester from the auto store, it has a glass window so you can see the spark its a very handy tool. I take the fuel line off at the filter to see if Iam getting fuel, But you must be careful if you do this, and dont let the fuel and sparks get together. Might be better just to open gas cap and hold ear close while someone turns the key on, if fuel pump is working you will hear it run for just a few seconds. Or as long as he is at the autoparts store .. get a cheap vacum/fuel pressure gauge too. That wil avoid that entire spark fuel boom thing. nipper Quote Link to comment Share on other sites More sharing options...
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