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Thread: 818 won't start

  1. #1

    818 won't start

    Hey guys, I'm running out of ideas so hoping you can help.

    The car was running poorly so we brought it to a WRX tuning shop. They spent a lot of time with it, fixing little issues as they came across them and tuned the car. It made about 215 rwhp on a basically stock engine.

    Then I towed the car to a detailer to have the gel coat buffed. He finished up a couple of weeks later and as I was on my way with a trailer to get the car, he called me and said he was just warming I up and it just died. It cranks, but won't fire. We pushed it onto the trailer and brought it home.

    This was last weekend. Now we are spending the day again working on it.

    Here's what we've tested.
    No spark. We pulled a coil and plug, touched the head and cranked. No spark.
    We smelled fuel in the exhaust but decided to pull a fuel rail. It's getting fuel and the injectors are firing when cranked. So we have no spark but have fuel. We can also hear the fuel pump priming.

    We checked every ground we could find on the pin outs for the ECU. All tested good.

    The Cobb Accessport reads cranking RPM, so I think that proves the crank position sensor is working.

    We've had the battery hooked up to a charger.

    We swapped the 15a #fuse with another 15a fuse.

    I even tried a new ECU, no dice.

    We are at a loss.

    Any ideas? I'm think it my be a grounding issue that we potentially missed.

  2. #2
    Senior Member Bob_n_Cincy's Avatar
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    Hey Guns
    Great to hear from you. It's been a while.

    Did you have any engine codes?

    It sounds to me that has to be something in the spark firing circuit. I say that because if it's firing injectors, then it should also be firing spark.

    If your sure there is no spark, I would say it's and electrical problem. The coils should have 12volts on the Red/yellow wire when ever the key is on. The black/yellow should be at ov at the coils when the key is on.

    If there is a spark, then possibly the car got rolled backward in gear and jumped the timing belt.

    Bob
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  3. #3
    Make sure the Grounds from the engine to the frame/battery are ok.
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  4. #4
    Thanks for the replies guys. I was deployed for 6 months over the summer so the progress on the car stalled for a bit (pun intended). It's just weird that it was running fine and just quit while idling. I'm thinking something either died or worked it's way loose. No codes are being thrown related to this either. I'll check the coil connectivity and see if it's at least getting a signal.

    Rick

  5. #5
    Do a continuity check to a know working ground to the coils as well.

  6. #6
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    Make sure the connections at the MAF (and the MAF itself) are all good.

  7. #7
    Quote Originally Posted by ben1272 View Post
    Make sure the connections at the MAF (and the MAF itself) are all good.
    Yea I checked that. It's even a new MAF. Plus the car would start even with the MAF disconnected, it would just run poorly. Right now the car cranks, just doesn't start.

  8. #8
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    Alarm system? Immobilizer of some sort?

    I second (or third) the check the ground. Did you provide all the grounds recommended by FFR and did a good job cleaning the frame of paint,etc., to ensure good connections? Might be worth loosening and re-tightening all of them.
    Last edited by ben1272; 02-18-2017 at 12:10 PM.

  9. #9
    whats the model year of the donor/engine.

    respectfully,

    John

  10. #10
    Quote Originally Posted by ben1272 View Post
    Alarm system? Immobilizer of some sort?

    I second (or third) the check the ground. Did you provide all the grounds recommended by FFR and did a good job cleaning the frame of paint,etc., to ensure good connections? Might be worth loosening and re-tightening all of them.
    Yea I think I need to go through the grounds again. The car had a factory alarm system, could that keep it from starting? Not sure how it would work in the 818.

    I'm reasonably sure the grounds were good, but it's probably worth re-checking/doing them.

    The donor is from a 2002 WRX.

  11. #11
    2002 was the factory Alpine alarm system which didn't kill the engine. The Immobilizer didn't start until 2005 generally and 2006 on the WRX..
    See: http://www.cars101.com/subaru/keyless.html#alpine
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  12. #12
    The coils ground to intake manifold via the two large ring terminals. if you got power and ground to the coils, you should check them with a ohm meter. if you have a ociliscope you should check the coil triggers from the ECU should be a waveform signal. might be worth scoping the cam position sensor as the ECU uses that for phasing. did the injectors work while cranking? or just priming pulse.

  13. #13
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    Quote Originally Posted by GUNS View Post
    Yea I think I need to go through the grounds again. The car had a factory alarm system, could that keep it from starting? Not sure how it would work in the 818.

    I'm reasonably sure the grounds were good, but it's probably worth re-checking/doing them.

    The donor is from a 2002 WRX.
    The link Sgt. Gator sent says: OVERRIDING the alarm when you don't have a Remote to disable it.
    If you don't have the remote put the key in the ignition and turn it on and off three times and the car will start on the 4th time

    Sgt Gator also said this alpine system doesnt immobilize, but this paragraph certainly makes it sound like it does! Try it...easy to do.

  14. #14
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    https://forums.nasioc.com/forums/sho...d.php?t=233461

    Read this thread too regarding the alarm.....your unit may have a relay that kills current to the ignition/fuel pump. There seems to be some confusion though.

  15. #15
    Thanks again for all of the ideas so far. Unfortunately, the car is at my Dad's house which is 1.5 hours away. I had my Dad try to disable the alarm and that didn't fix anything. I'm going to check the continuity of the coils this weekend. I'm thinking about just replacing the cam position sensor as well. New ones are only $30 on Amazon. Alpine, like you said it seems that a failed cam position sensor can lead to no start situations.

    The injectors are working while cranking.

  16. #16
    Senior Member STiPWRD's Avatar
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    I used on 02 wrx donor and completely removed the alarm system without any issues. GUNS, you mentioned you don't have any codes related to this but does that mean you don't have any codes at all or just none that you think would stop the engine from starting? Surprisingly, there are some codes that seem unrelated but can actually prevent the ecu from firing the spark plugs.

  17. #17
    from the wiring diagrams is looks like the factory alarm is only a starter interrupt, however There is a feed into the ECU on pin A16 should be yellow that is controlled by the interrupt relay. looks like one could short pin 2 and 6 on the interrupt relay to bypass it altogether (WB/WR wires).
    The RY wires on the coils are the 12v source wire they trace back to fuse #11 on FB20 G/R wire color. If you look at the schematic on WI-69 from the Factory Service Manual it shows the factory alarm system interrupt relay diagram If you need a copy let me know.

    Respectfully,

    John

  18. #18
    Sweet, thanks I'll check that out.

  19. #19
    So I found the keyless entry control box sitting on my parts shelf. Are they and adverse effects by having that thing disconnected?

  20. #20
    The key less entry module ties into the security module which controls the interrupt relay. I would try bypassing the interrupt relay. The Cam Sensors are pretty robust VR sensors and if your getting the injectors to fire I suspect it's functioning correctly as the ecu would use the cam signal to fire the injectors.

  21. #21
    For grins and giggles you should check if any of the sensors have gone bad and are grounding the input.

  22. #22
    Senior Member STiPWRD's Avatar
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    If there was an issue with the interrupt relay (i.e. anything related to the security system or keyless entry) wouldn't that prevent the starter from cranking? Since the car is able to crank, I'd suspect something else. I mentioned above that I'm using the same harness and ECU (02 wrx) and I completely dieted the security and keyless entry modules from the harness - the 818 runs and drives without any issues. I bypassed the interrupt relay by shorting it out.

    I suggest checking all of your engine codes. Something as simple as a malfunctioning coolant temp sensor will prevent the ECU from firing the coils. A few other codes will also prevent the engine from starting.

  23. #23
    The interrupt relay also connects to the ECU. If it's bypassed should be no issues. I am not sure how his harness is wired so I recommended bypassing the interrupt at the relay so the high/low feed into the ECU is also bypassed. Agreed if interrupt is not bypassed and stuck open the starter should not work unless it was bypassed in some manner. That's why I offered up the pinouts for the coils as well. Seems odd to fire the injectors and not the coils.

  24. #24
    Senior Member STiPWRD's Avatar
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    I agree it is odd, it leads me to think it's one of the following issues:
    1. Bad plugs
    2. Bad coils
    3. Bad wiring from ECU to coils
    4. ECU isn't firing coils

    #1-3 can be tested by removing the plugs and coils from the heads but keeping them plugged in to the harness and supplying 12V at the wiring where they attach to the ECU. If this generates a spark in each plug then the issue is most likely #4. There's either a fault or check engine code that's preventing the ECU from firing or the ECU may be damaged (but this is unlikely since it can communicate with an AP).

    coils.jpg

    One other possibility is a bad connection at the SMJ connector; much of the key engine wiring runs through this connector.

  25. #25
    I looked through the ecu pinout it list C18 as coils ground it grounds to the same large rings on the intake manifold as the coils. (looking at the spaghetti of wires glade I made my own harness with stand alone)

    Make sure your 12v supply to the coils and ecu are active during cranking as well... been there before...

    oddly the pinout states that the coils fire on a 12v waveform but they fire perfectly fine on a 5v logic output.

  26. #26
    Thanks again for all of the inputs guys. I'm going to poke around this weekend and see if I can make some progress.

  27. #27
    So I got to spend a little time with the car yesterday. The coils are receiving 12 volts during crank, just no spa I unplugged it, but that didn't change anything. I tried to do a hard reflash, but I kept getting an error saying to connect the initialization connector even though it was connected. Here's the only code: P0183 Fuel temp sensor high input.

  28. #28
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    Almost sounds like you have some wiring issues here. There are a couple of harness connectors that connect the rear harness sections to the front harness sections (big white rectangular ones that have like 20 or 30 wires going into them) and these can actually be plugged-in wrong. Meaning, there are two large male connectors and two large female connectors. The male-female connectors connect as a pair, but the male from one connector pair can be plugged into the female connector of another pair. Unlike most other connectors, there aren't ridges that make each pair only work together. I did this at one point before I customized the wiring harness.

  29. #29
    Senior Member DodgyTim's Avatar
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    Quote Originally Posted by Hindsight View Post
    Almost sounds like you have some wiring issues here. There are a couple of harness connectors that connect the rear harness sections to the front harness sections (big white rectangular ones that have like 20 or 30 wires going into them) and these can actually be plugged-in wrong. Meaning, there are two large male connectors and two large female connectors. The male-female connectors connect as a pair, but the male from one connector pair can be plugged into the female connector of another pair. Unlike most other connectors, there aren't ridges that make each pair only work together. I did this at one point before I customized the wiring harness.
    The description that it was running on the dyno and was warming up when it stopped would indicate a component failed or a connector came loose, rather than incorrect wiring in the first place

  30. #30
    Hey guys, we got some time to work on the car over the weekend and still can't figure it out. Of note, the coils are receiving 12 volts.

    The interesting thing is that I can't flash the ECU with the accessport. The AP kept telling me to plug in the Blue connector to the white flash memory connector, even though it was. We tested the flash memory connector and it is not receiving any voltage. That connector has two wired, one goes straight to the the ECU and the other goes to the diagnostic connector. I am assuming that it uses the grounds from the the diagnostic connector, so we tested those and they were both bad.

    As I was digging around, I found two wires that I assess to be grounds that were removed from a connector. They were taped up together bundled with some other wires. I'm pretty sure the shop I had the car tuned at did this, but I'm not sure why or where they came from. While it's odd, I'm not sure any of this would cause the problem I'm having.

    Here are the wires in question:


    Any thoughts?

  31. #31
    Yes, I love Technology aquillen's Avatar
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    Reading back through your posts on this -

    I've revisited this thread a couple times, expecting you'd have it by now. It continues to sound to me like you may not have a ground to the coils. If you absolutely ruled that out then I missed it.

    You have fuel injection. I think that means move on from the ECU itself for now. I never discount anything being looked at again later, until you fix a problem, but you also tried another ECU. I think I'd move away from the ECU itself and look around. With injection pulses working, whether or not you can program the ECU, or go into program mode, is probably not your main problem here, nor likely even associated to it (again I say probably).

    About the ECU spark and inject logic. Given the ECU is firing the injectors, I expect the ECU should also be issuing the spark pulses. So until you find out why no spark I would stay focused RIGHT on that circuit. I think it very unlikely that any ECU designer/programmer would build a logic flow that would inject fuel but not then also supply spark, because that would eventually create a fire hazard - putting fuel out of the tank into the system and not trying to burn it. And in my experience micro-controllers and microprocessors generally don't fail such that they run part of this kind of logic and not the rest of it (could happen, just way down on probabilities) - (and you tried another ECU).

    -------------

    You've almost convinced me so far you have a ground problem to the coils, so I'm going to detail some different ways to test and validate the ground. If you are not getting spark command pulses from the ECU to the coils, that is a matter of continuity checking all four of the wires from the ECU to the coils - but just seems very low on probabilities to have all four gone at once, so check it later.

    I would start with using a simple lamp test. Rig up a tail-light bulb (good old Edison filament, not a new-fangled LED), and connect it to the +12V and ground pins of one (each really) coil's connector and verify it fully lights when +12V is on. This will load test your power and ground circuit paths in one step for that coil. The following will cover other tests but also help explain why this lamp test is worth the time - until you get this sorted.

    A poor ground connection, sometimes -rarely- but can look pretty good using an ohmmeter to test it. But when you put the normal power flow to the circuit it may have enough resistance to no longer provide true ground. Test this way to ensure it is holding ground when "powered up":

    You also mentioned more than once you have +12V on the coils. I don't read where you verified you have solid grounds to those spark coils. Were it me, I'd get the +12V turned on at the coils, and (a) measure and see the +12V on the coil(s) and then immediately also measure the ground side of the same coil(s) and verify it is right down at 0V to no more than maybe 0.2V and of course not +12V. Make sure you aren't losing the other side of your meter to ground during these tests.

    Here is another potential fooler when testing a circuit that is marginal somehere - the current flow is only going to happen for a pulse moment for each spark event. So the 12V and ground connections only have to "perform" during that moment. The coil is not actually going to flow current through those paths except just at the moment of spark production. The typical spark production (I haven't scoped a suby coil so generalizing here), is just before spark is needed, turn on low voltage (12V) to build current flow into the coil (primary), it builds a magnetic field over short time period that envelopes the primary and secondary coil windings, then turn off the current. The field rapidly collapses and the high voltage windings side of the coil generates the almost instantaneous high voltage spark. What this complicated story means, is checking the ground side of the coil in standby is also not a 100% foolproof validation that the ground is really solid.

    ------------

    Not to insult you, but just in case, some guys who are not heavy into electrics will set an ohmmeter to a high ohms scale to measure resistance. When chasing grounds and continuity, use the lowest ohm setting available (for example - use 200 ohms, not 20,000 ohms). Otherwise you chance looking at a poor connection, say 500 ohms, and on the meter it may look ok. Digital meters are harder to get fooled by this mistake, but analog meters will get you this way...

    Not to insult you, but just in case, if there is paint under the ground lugs to the engine case/manifold, wherever, undo that situation. While the bolt or nut, whatever should still do the job, this just is not the way to do such things, on the engine, chassis, in the cockpit, anywhere on the vehicle.

    Questions -

    How are you determining you don't have spark? Plug against engine case and looking? Do you trust those plugs? If you are using this method, try a new plug or one you know will "show you" a spark if it is there. I've seen fouled plugs that didn't look very fouled but they would not spark - shorted in the body... Also if you are pumping fuel in, some of it will be blowing out the spark hole during cranking - if you do get a spark look out! (but you know that).

    Those two wires in you picture look either pink-black or violet-black. I scanned all my wiring spreadsheet ('03 H6, but still...) and then scanned through 2002 Impreza wiring and only found one reference to pink-black (one of the injectors). I probably missed it somewhere on a page if it is one of those colors. But again, it was working so I wouldn't go after those until you give up elsewhere. Would be good to identify what they are though.

    Lastly as others said, it was working so either you have a connection gone loose or a major mechanical like jumped time (but you'd have spark so you are painted into the fix the spark corner first). Locate each connector of the injectors' circuit paths (ground, +12V and finally yes - the ECU pulse lines), pull them apart, locate the pins and verify not pushed back in the shell.
    Art Quillen

  32. #32
    Yes, I love Technology aquillen's Avatar
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    Let me add another possibility here. I believe (not positive - it could be a +12V pulse) that the ECU outputs a momentary ground pulse to a coil to generate each spark event. The ECU has several grounds supplied into it, and they don't necessarily all tie together INSIDE the ECU case. This allows some to be "clean" or "not-noisey" grounds for sensor circuits, while other grounds handle power pulse actions such driving injectors, spark circuits, solenoids, etc. This means one missing ground could create specific problems and not interfere with other ECU functions.

    Without going into the ECU and tracing the internal grounds to the power transistors that drive the spark commands, we don't know off-hand which ground comes into the ECU for this particular job.

    Bottom line then is if a ground TO the ECU itself is not good, and happens to be for your spark circuit, it could be your culprit. My H6 has 10 grounds that I've traced into the ECU. Most come in through the B83 connector. I see the 2002 Impreza also uses the B83. A lot of people are cutting this out and tying those wires together. You may be smart to take some time and examine your B83 for pushed pins, damage, or the wires you took out of it and spliced together - whatever you did there. Even a pushed pin into the ECU that is one of these grounds would get you this problem.
    Art Quillen

  33. #33
    Yes, I love Technology aquillen's Avatar
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    Let's pretend it is a ground to the ECM that is loose. Studying the 02 Impreza wiring, I'd put my first dime on the one marked in red in the attached drawing.
    IgnitionGroundToECM.JPG
    Art Quillen

  34. #34
    Senior Member Steve91T's Avatar
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    Hey guys, I'm GUNS's brother and have been trouble shooting this car with him.

    We removed the ground strap that bolts to the tranny, cleaned it and reinstalled. We did the same with the ground that is attached to the drivers side intake manifold. The grounds were good, solid connections with no paint, it we still made sure. We removed a coil electrical connection and verified 12v with the key on per instructions someone posted in this thread. If the coils are getting 12v, wouldn't that rule out a ground issue at the coils?

    We also physicaly checked every ground we could possibly get to. There are a couple in the trans tunnel that we can't get to. We also removed the large connector with like 30 wires (forgot what it's called) and checked the grounds coming into it, then on the ECU side, checked the ground there. Everything keeps checking out. We've also checked every ground using a wiring diagram coming into the ECU.

    We also removed the CPS and cranked the car. Got 0 RPM. Then we reinstalled it and cranked, we got a cranking RPM. This should rule out the CPS.

    The car detailer said the car was idling for a few minutes while he let it warm up when it just quit. That was the last time it ran.

    The plugs are brand new. I think the chances of all 4 plugs fouling at the same time are next to impossible, same with the coils.

    When checking for spark, we pulled a plug and grounded it to the engine while cranking...obviously we could not see a spark. Since we have fuel and it cranks without any signs of life, we can't have spark. As many times as we have cranked this engine, it has about the same life in it as if the coils were all unplugged.

    If the timing belt or chain broke (it's new and was replaced while he was building the 818, or just before), we would have piston to valve contact and the engine woild be locked, correct?

    I think it's time to replace all the plugs just to start ruling out the impossible.

    Can we use the light bulb trick to test the firing signal from the ECU to the coils?
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  35. #35
    One area that no one has discussed is the sensors. I have had two cars were a sensor failed/ shorted out and it caused the engine not to be able to run. If everything else has been looked at, try changing them.

  36. #36
    Senior Member DodgyTim's Avatar
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    Quote Originally Posted by Steve91T View Post
    Can we use the light bulb trick to test the firing signal from the ECU to the coils?
    No, the signal is too short/fast to light up a bulb, it needs an oscilloscope to see it. If you have access to one you can also check the fuel injector signal.
    There are small oscilloscopes that are about the size of an iPhone and cost about $60

  37. #37
    Yes, I love Technology aquillen's Avatar
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    The lightbulb test won't help on the pulse lines. From reading the service manual that line should be about 12V in standby though - so check you have that. When sparking, each line will pulse low for a very short time then back to high. Only an oscilloscope or other fast detect device would pick up the short low pulse.

    The ignition diagnostic steps in the service manual are pretty thorough and not complicated to follow, you should try that if you have not yet.

    I'm going to be in Greenville SC early May, looks like 1.5 hour drive? If you're still stuck I'd come by for an evening. PM me.

    Ha that is timing for you, I was typing mine and yours arrived 1st.
    Art Quillen

  38. #38
    Yes, I love Technology aquillen's Avatar
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    Did some more reading, this time Internet on this kind of problem. Camshaft sensor tells ECU when to inject fuel. "Crankshaft position sensor" tells it when to spark. So a problem in the crankshaft sensor circuit could be the culprit. Apparently this system will inject fuel and skip sparking if just the right things are missing. Trace that crankshaft sensor circuit out. Discussions also point to damaged teeth, missing teeth on the crankshaft sensor sprocket that passes that sensor.

    Someone also suggested putting a bit of oil in the cylinders if you've cranked a lot of gas into them and not burned it out... might be a reasonable thing to do. Teaspoon each maybe?
    Art Quillen

  39. #39
    Senior Member Steve91T's Avatar
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    We've replaced the cam position sensor because it was cheap and easy to do.

    The crank position sensor is sending an RPM signal. If it's sending that signal, then it's working, right? Isn't it just a magnet that reads RPM?

    We were able to remove the crank position sensor but left it plugged into the harness. I cleaned it and while it was still out, I had my brother crank the car while watching the Cobb. It showed no RPM. I then installed the crank position sensor again and we did the same thing. It showed cranking RPM.

    Do theses tests confirm it's working properly?
    Last edited by Steve91T; 04-19-2017 at 01:35 AM.
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  40. #40
    Ecu uses crank position sensor for rpm and cam sensor for phasing. Both are needed for fuel and fire in sequential fuel and coil on plug ignition otherwise it would have to run wasted spark semi sequential. I am assuming the ECU doesn't run batch fire injection under cranking conditions. The Subaru vr sensors are very sturdy (very noisy however) and don't fail very often as long as you used shielded wire for them and grounded the shielding on the ECU side you should be good to go with cam PS and crank PS.

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