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She won't start :(

Discussion in 'A3/S3 Forum (8L Chassis)' started by vanilla_ice, Oct 10, 2013.

  1. vanilla_ice
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    vanilla_ice Member

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    Hi,

    I have recently carried out the below using various guides for my AMK S3:

    replaced my injector inserts
    ultrasonically cleaned injectors and fpr
    replaced injector o-rings
    replaced inlet manifold gasket
    removed and cleaned throttle body
    replaced throttle body gasket
    replaced both valve cover gaskets
    replaced CCT gasket and half-moon - using tensioner tool
    deleted N249

    Put it all back together and now she's not starting. :( The engine turns over for less than a second, but generally sounds rough and produces the occasional pop (misfire?).

    I have checked with VAG-COM and the only fault found was 16395 - 16395/P0011/000017 - Ross-Tech Wiki

    I was able to clear the fault and it hasn't returned. I have tried starting it about 10 times, but don't want to keep trying unless I am making the problems worse.

    Is anyone able to offer some words of wisdom? I hope so...


    ICE
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  2. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    Your cam timing is out

    You need to check you have it set at TDC and the cams 16 rollers apart. But given the current code, it would appear it is not, however if it stays away, leave the car for a few hours and it will probably start

    The followers pump up when you remove cams and hold the valves open until they settle. Hopefully no contact has taken place...
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  3. vanilla_ice
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    vanilla_ice Member

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    Thanks for the reply Byzan.

    Neither cam was removed when replacing the CCT gasket and I am positive the chain didn't jump any teeth when loosened.

    A little lost when it comes to 'followers'. Where would the contact you mention take place? Valves and piston?
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  4. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    if you didn't remove any cams, i'd be checking you have connected things back to where they came from. because nothing I can see other than that should have been invasive enough to cause non starting. Don't worry about the contact,that is not an issue because you didn't remove cams
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  5. vanilla_ice
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    vanilla_ice Member

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    Small update.

    Forgot to mention that I reset the throttle body using VAG-COM once everything was back together.

    Having left it for 24 hours I have just tried again. Managed to keep the engine running by pressing and releasing the throttle. I then stopped pressing the throttle and the engine continued to run but the revs kept fluctuating. When the revs were dropping I could hear miss fires.

    I haven't re scanned for faults yet. Does the above help diagnose what's going on or what could be the problem (and solution!)
    #5
  6. vanilla_ice
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    vanilla_ice Member

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    Ok. Unplugging the MAF allowed the engine to run albeit roughly, but the revs didn't fluctuate. It did bring up a light on the dash so will check and clear the fault.

    Next up is inspecting the coil pack wiring. The engine is rocking quite a lot when running and there is also a smell of petrol. Both are common with coil pack failure I believe? The coils are less less than a year old as they were replaced under the Audi recall.

    Are there any other sensor I can unplug that will help troubleshooting?
    #6
  7. vanilla_ice
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    vanilla_ice Member

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    So I inspected the wiring past the N75 wiring and re-insulated all the cracks I could find. I also cleaned the spark plugs.

    Then tried turning it over again and was just as before. This time I kept cranking the starter even after the engine had stopped. After a short while the oil can icon appeared on the DIS so I stopped. I have checked oil level this is fine. Does seeing the oil can meaning anything else?

    With the MAF unplugged the engine still runs, but very rough.

    I then had a another VAG-COM scan for faults. Only the low MAF signal (caused by unplugging) was found and then cleared.

    I then clicked the 'View Readiness' button within the engine controller. It was show that the following are 'Failed or Incomplete':

    Oxygen Sensor Heating
    Oxygen Sensor(s)
    Evaporative Emissions
    Catalytic Converter(s)

    I have nothing to compare this with. Is that normal? Bearing in mind the car now hasn't been run for a week.

    HELP! If anyone can offer any suggestions I would greatly appreciate it.
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  8. darren t
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    darren t Member

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    check the wiring too vvt unit if not take rocker cover off with engine at tdc and cams shoul have a notch on them and the cam caps have arrows on them see if they alighned here's mine...

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  9. vanilla_ice
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    vanilla_ice Member

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    Cheers darren t

    On the face of it the VVT's wiring looks to be OK. Will remove some of the wrap and take a further look.

    When I compressed the cam chain tensioner the cams were not TDC. I presumed they only had to be TDC if removing a cam or replacing the tensioner so the 16 chain rollers could be counted. Could that be where I went wrong? I still swear the chain didn't jump any teeth etc.

    Would a timing issue throw up a recurring fault in VAG-COM?

    What is the safest way to get the cams to TDC on my own? If the cams are not lined up with the cam caps, how do it get them to line up? Is it an inlet cam out job?

    Do I need new valve cover and cam chain tensioner gaskets if taking the current ones off? The current ones are only a week old.


    Sorry for all the questions!
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  10. darren t
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    darren t Member

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    i would advise a garage mate if you don know were tdc is but here's a picture for refrence.........basically I thing the chain hasn't got 16 rollers between the 2 notches then there's your problem ......
    you've have changed inlet manifold injector inserts ect nothing dropped in there did it???? I think the cam chain has not been put on properly ie slack at bottom of tensioner!

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  11. vanilla_ice
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    vanilla_ice Member

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    Thanks mate. Sorry for all the questions. Even if I only diagnose the problem it will hopefully save me a bit if it does end up going to a garage.

    I'm hoping to check the timing later today. Don't laugh, but do I rotate the engine form the crank or the cam pulley?

    If there isn't 16 rollers can I expect there to be bent valves? If timing appears to be OK, how can I pressurise the tensioner?

    I changed the inserts while the inlet manifold was off the car. A bit a cr@p did fall in, but I sucked it out with a Dyson. It looked clear before it went back together.


    Thanks again.
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  12. darren t
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    darren t Member

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    Crank buddy!! And if there isn't 16 rollers then I'd expect there too be bent valves but then again if you can rotate engine by crank 2 then theres been no contact,The crank pulley it has a slot on it and the casing has a slight mark on it no need too remove bottom pulley yet!! Il go get a pic as mine is off just waiting for an ecs tunning Cambelt kit!
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  13. darren t
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    darren t Member

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    There's the mark on pulley should alighn with a small groove on the casing use a bright torch you'll see it alighn crank then check the cam shaft sprocket is alighne with rocker cover...then take off rocker cover and check notches with the arrows and we can go from there!

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  14. vanilla_ice
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    vanilla_ice Member

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    Cheers for that. I didn't get round to checking the timing marks, but did have another scan with VAG-COM.

    I ran the output tests within the engine module and they all said 'short to ground'. Could this be a clue to anything?
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  15. darren t
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    darren t Member

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    hae you checked the earth on the rocker cover is getting a good contact by coil pack 1??
    definatly not timing buthe looks of it then going too be bad connection somthing not connected what about cam sensor did this get connected back up?
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  16. vanilla_ice
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    vanilla_ice Member

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    Yep, quadruple checked that earth. Have just removed all connections I disconnected and sprayed some contact cleaner on them. I have checked fuses and checked for fuel flowing on ignition by removing the return hose. All seemed in order. Still not been able to check timing.

    Im wondering if I have damaged either an injector or coil pack. I have VAG-COM and a multi meter. Anything I can go measure?
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  17. vanilla_ice
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    vanilla_ice Member

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    BUMP

    Had another look over the engine today. I started by cleaning up the battery terminals and then checked more of the wiring for cracked insulation / shorts, but found none. I noticed that when misfiring air was coming out of the inlet manifold gasket. So re-torqued all of the bolts (from centre outwards) to an indicated 10Nm. Also noticed that the injector for cylinder 3 (third from left) was leaking. So removed, cleaned and re-seated.

    Having sorted both of these issues it still doesn't idle right, with the revs hunting between 600 - 1500 rpm. At the higher revs the engine sounds normal and wasn't shaking like it has been, but when the revs dropped there were still a few pops and bangs. Going by the flashes I could see through the injector inserts(!) the misfires mainly seem to come from cylinders 1 and 3. Still no error codes.

    I am now quite confident that all cylinders are getting fuel and a spark, but I'm left questioning the timing. The garage I normally use said I may have "slipped a tooth on the compression stroke"? So I am thinking that is the next logical thing to check.

    When trying to find TDC by turning the crank, do I want the plugs out to make it easier to turn? Should I need a breaker bar to rotate the crank?
    Last edited: Oct 19, 2013
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  18. boost-addict
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    boost-addict Member

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    when i started reading your list of what you have done, i thought inlet manifold gasket. for the price of what one costs go get one an redo it. i bet you havnt seated it right,

    which is confirmed by the air that you can hear out the manifold. might not fix the problem but if your sucking air in that the ecu hasnt accounted for, itll run like a bag of... and just not run generally.
    unplugging the maf turns the ecu to closed loop and other sensors, which is why your getting at least something out the engine.
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  19. darren t
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    darren t Member

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    yes use big bar and remove spark plugs! You shouldn't be able to see any flashes unless injector inserts have been fitted wrong..
    check engine is at tdc then I would remove inlet manifold again and check all my work with a tooth comb!
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  20. vanilla_ice
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    vanilla_ice Member

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    Thanks boost-addict. My last update was with the MAF connected, sorry if I didn't make that clear. I haven't tried with MAF unplugged since tightening the gasket and re-seating the injector. Would unplugging the MAF help diagnose the problem at this stage?

    Is there a reasonable chance the manifold gasket has been damaged then? You wouldn't recommend retorquing to say 12Nm?

    So still not necessarily timing?
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  21. boost-addict
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    boost-addict Member

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    as it was early in the morning i missed the flashes though the injector inserts, but same thing, if theres any air thats allowed to be sucked in then it won't run correctly.

    maybe the air you could hear was coming from the injector inserts. but if thats the case then you could have found the problem
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  22. vanilla_ice
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    vanilla_ice Member

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    The flashes are happening inside the inlet manifold. The new inserts have been thread locked in place. They were screwed as tight as I dare without breaking then. I had to replace one insert before refitting the manifold as I over tightened it. I think manifold gasket is more likely.

    Other than tightening from the inside out at 10Nm, should I be doing anything else?
    #22

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