Missing after hard acceleration

Discussion in 'Technical' started by andyz, May 6, 2017.

  1. andyz

    andyz Member

    My car was running rich and missing after hard acceleration.After start and cruising it would remain sweet and drop to a nice idle, But after hard acceleration would develop a miss and idle high. After new coil packs and plugs and fixing an inlet manifold leak car was great for one day.Problem now back,any advice would be appreciated. Thanks in advance. Andy.
     
  2. andyz

    andyz Member

    ptu?
     
  3. 90TTZ

    90TTZ Back From The Dead

    Just need some clarification. Do you mean it was running fine and then after one hard acceleration it now is idling high? I would be looking for a boost leak.
     
  4. andyz

    andyz Member

    No, seems to be intermittent. One or two wot runs sometimes no effect,But if I continue to do this it will develop a miss and idle rough. sometimes there is a rich running smell but not always. if left overnight it seems to start sweet and idle nicely once warmed up.took it for a two hour drive yesterday without any wot runs and it stayed sweet. The car runs a pod filter,z1, intercoolers,hks 2510 tubos,sard 540cc injectors,and nistune. it was tuned at uas 18months ago and was making 240rwkw.
     
  5. andyz

    andyz Member

    car is a 92 tt auto
     
  6. 90TTZ

    90TTZ Back From The Dead

    Can't get yourself another set of coils to try?
     
  7. andyz

    andyz Member

    probably not as it took just about all my spare cash with what I have just done.all parts used were new,I also replaced my clutch fan and flusher rad and replaced coolant. Broke for a little while now.:eek:
     
  8. East Coast Z

    East Coast Z Well-Known Member

    Something's wrong with your engine. :(

    Comparing your modifications & rear wheel output to a TT fitted with stock air filtration system, stock intercoolers, stock turbo's, stock injectors & Nistune & makes 243rwkw on the same dyno.
     
  9. andyz

    andyz Member

    Yes I was not thrilled with the result. But I did what I thought was the right way to go,Which was take the car to a workshop that work on zeds often. I supplied tubos,injetors,and intercoolers.They checked motor and deemed it good to proceed with the work. which was remove motor,fit all the hardware do deletes supply and fit nistune,and tune.F@*K nothing change from 12 gand. and had to ring a week later to ask for my original turbos back,never got my air box back and was told when I asked for my injectors that no one ever wants them back. there was more to this as well. story ends that I will never go near UAS again.Will try mrc with this problem if no one on here can help.
     
  10. East Coast Z

    East Coast Z Well-Known Member

    Here's the thing........

    The majority of forum members would like to assist with your problem/s, however rather than guess as to what the problem is, there comes a point in time where diagnostics are required.
    To diagnose the issues correctly you require a plan of action, somewhere to test the vehicle, proper diagnostic tools & fault finding abilities plus the Nistune software.
    Where are you located?
    Perhaps a tech day could be organised.
    The first thing that should of been done prior to purchasing any upgraded parts, was to perform an engine compression check.
    Was this done?
    If it was.
    What were the results?
    If it wasn't, then it should be done now.
     
  11. East Coast Z

    East Coast Z Well-Known Member

    Am I reading this correctly?

    You supplied the turbo's, injectors & intercoolers.

    They checked the motor prior to performing any work & verified it was in suitable condition to proceed.

    They removed the motor from the vehicle.
    Removed & refitted all the hardware.
    Completed deletes.
    Refitted the engine to the vehicle.
    Supplied & fitted nistune & tuned the engine.

    For $12,000. :eek:

    There must of been more work completed than the above.
     
  12. Madcow

    Madcow Active Member

    If that is the case, I could do that in about a week by myself from home!

    12k for a weeks worth of work, yes plz! :agree:
     
  13. andyz

    andyz Member

    No that was it apart from replacing driveshaft center bearing and engine mounts, both of which they supplied. They did charge a total of 6 hours labour for (and this is a quote from invoice)No start. check ecu outputs,fuel pressure and spark.Found injectors failed. remove inlet and injectors,manually cycle injectors individually until working. refit injectors and inlet.Though I had the injectors cleaned and checked prior to supplying them.There were some parts as well. coolant pipes, gaskets, heater hoses o2 sensors,power steering pressure line, plugs and a boost tee.But yes as stated before I was not totally thrilled with the whole thing including the result, which now I have dug out the paperwork was 232.3 RWKW . But that is in the past all I want to focus on for now is to get this thing running nice again.Not a mechanics bumhole myself but I have a go at what I can(not much).Once again thank you to any who take the time to give any informed advice or educated guesses.
     
  14. andyz

    andyz Member

    Compression was 130 to 140
     
  15. 90TTZ

    90TTZ Back From The Dead

    Definitely not suggesting to go out and buy a set. Surely you have met some other enthusiasts who would be willing help out?
     
  16. MikeZ32

    MikeZ32 das Über member

    Sorry... how much???!?! :eek: Does every hour of labour also include a high cost escort who also gives you a "good time"?


    That's like a $400 in parts at the very most... since the engine is out anyway engine mounts are a no brainer and shouldn't add to the labour.
     
  17. East Coast Z

    East Coast Z Well-Known Member

    Re: Engine Compression

    The standard compression pressure of a TT engine is specified at 171 psi.
    The minimum acceptable pressure is 128 psi.

    The low compression figures would account for the low RWKW figure on the dyno.

    Where did you get these compression figures from?

    Were you aware that your engine was suffering from low compression prior to authorising the work on your engine?
     
  18. ZYTRAM

    ZYTRAM Formerly known as martini_Z

    I'd start by doing:
    - Boost leak test
    - Check for plug fouling as result

    12k is a rip. Considering the engine came out, it's possible a hose clamp is loose, making itself apparent under boost.
     
  19. tassuperkart

    tassuperkart Its a lie I tell you!

    Those are little turbos TBH. barely an upgrade. But anyway.
    Importantly, what boost pressure for that power reading?
    E
     
  20. CHILI

    CHILI Indestructable Target

    Unfortunately, this is just one more unhappy story(emerging from the aforementioned W/Shop).:eek:
    MRC may well be your BEST solution(it certainly won't be any worse than you have experienced thus far).:(
    Good Luck Mate(let us know the outcome).:zlove::br:
     

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