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Hello, I have a 2009 subaru forester with a 2.5L 4 cl non turbo engine.
It will crank but NO SPARK until I attach my battery cables set at 15 amps. It will then spark and start immediately and for the rest of the day.
In the morning it will not spark.
The details of the problem are many but over the course of time I have replaced the following, The Battery, Plugs, Wires, Coil, Crank Shaft Positioning Sensor. The problem may be related to the PARISITIC CURRENT DRAW that I am also troubleshooting.
I hesitate to list all the symptoms and troubleshooting that I have done hoping someone will suggest a likely cause for my issue. it seems to be unique.
I hate it when my mechanic says" I've never seen anything like this before" !! any direction you may offer would be appreciated.
I think I would start by making sure my battery is good and fully charged. If that is good, id test the battery ground, where it meeta the chassis, or wherever. Check that with a voltage drop test.
For the parasitic draw, what info so you have in that? What is the current measurement and how long did you wait for modules to shut down when you took it? Some vehicles take more than an hour to shut down or could be running a evap natural vacuum leak test that can trick you. Not saying that's the case here, just throwing it out there.
I have the issue with a fully charged battery and when not charged. I have been plotting the voltage drop that occurs over night. it may read 12.4 V down to 12.2 volts. but that seems to be a second problem.
My main concern is the no spark. I changed the Coil , wires, plugs and Battery as a matter of troubleshooting. my coil has the built in ignitor so that also has been replaced. ( It is my understanding ) that the Crank positioning sensor induces the coil to fire in the cranking rpm range, The computer induces the coil after starting. this is why i changed my crank positioning sensor also. no help. the point that truly confuses me is that even with a battery at 12.4 volts there is no spark, When I attach my Jumper Cables to the battery set at 15A the car starts immediately. I am not charging the battery, the battery is not low. I've looked for tight and loose wires a hundred times but cant influence the issue. I have little automotive background but comprehend the electronics.
More background. This first happened last December, out of the blue the car wouldn't start. I changed the Battery, coil and igniter ,wires and plugs the problem went away and all was well for 6 months. This summer the problem occurred 1 time. I jumped it and it has been fine until recently, as the weather has cooled It has become a daily problem. as I say, after I get it running it will run and start fine all day. it will not start in the morning. even with diminished voltage, shouldn't the coil still fire?? I am seeing 2.4 volts at the coil signal wires (reference). I was looking for 5V but I saw on Line that 2.4 was normal. really not sure about that point. ???
I've been getting very varied readings, very unstable readings, I cant be decisive with the info I have seen. I think because of the point you make about things running and shutting down in the background. I have learned recently from a UTube channel how to properly let the computer go to sleep before testing. I am just into that process now and hope to find some definitive information. I did unplug my rear windshield wiper fuse, I saw that this was a common problem for my car. I do have a problem with that wiper over feeding and perhaps trying to correct it's self?? just looking at that now. thank you.
The fact that the jump fixes the problem makes me think that your battery is not providing enough current to make everything happen, if that's the only think you are changing to get it to start.
Have you performed a voltage drop test on the battery ground to chassis and block? With your meter set to voyage, you put one one lead on the battery neg post and the other on the other end of the ground wire/cable while someone cranks the engine. This has to be nearly zero volts or you'll have problems. Visual inspection will not show an issue here.
For a parasitic draw test, you have to use your meter in amperage mode in series with the cattery neg cable and see how much current is flowing through it with everything off. Checking voltage after resting can fool you. Current is the one you want to see here. I test every battery that comes in my bay and most of them are under 12.4v, even after doing the test within minutes of shutting the engine off, on brand new cars. You want to see less than .050a, or 50mA on this one. Some say less than 30mA. The last bunch that I've done have been about 8mA.
Paul definitely has videos out there on this and other techniques of draw testing.
I'm not sure what else would cause the jump to be the factor that makes it start if anyone else has any other ideas.
Thanks for that information. I did as you suggested and measured ( min-max) 0.000v - .411v avg. .032v.
I began to hook up incorrectly with my meter in series between the neg. post and removed neg. cable and in the voltage setting. I was surprised to see 12.2 volts. I was surprised to see a reading at all hooked up in series along 1 leg of a wire.
Are these readings out of line? I have an appointment for Friday at the dealership. I'm in deep with this one.
Correct. If you used the milliamp setting when you hooked it up, it may have exceeded the rating and blew the fuse, depending on the meters mA rating. They are usually pretty low. You'd want to use the 10a option for this test.
Took my car to the Subaru dealer today gave the tech a detailed description of my no spark problem and what I had seen and done to troubleshoot. Gave him a list of components that I had changed out. After an hour diagnosis he gave me a printed report that said my alternator belt should be tightened and I need new tires. $99.95
I'm a little lost with where we are at with this. Did you ever confirm a parasitic draw using the meter like in the video, on the 10a setting? Does the car start right away with a jump or does it have the delay that you mentioned?
The car is in the shop. I gave up. The tech. is as confused as I am. says he never saw anything like that ( my biggest fear).
Yes it starts right up with a jump, maybe ECM issue????
my point with the meter is that the video is wrong. in the 10A setting that he is in, he shows 0.25 on the meter screen. he reads it as 25MA. it should be read as 250MA. in that 10A setting.
