Horrible warm idle

  1. L-plater Joined: Aug 2014 Posts: 36
    #1
    Hello everyone, I am looking for assistance because I have an annoying problem since I bought my 106 XSI.


    At cold engine it runs absolutely perfectly! nothing, verry smooth and nice, perfect!

    Then, i shut engine off 2 minutes and restarting (so warm engine), idling goes to 1200rpm and when i accelerate i got a hole...like its runign pig rich, and if i go WOT nothin happens, just a big acceleration hole...


    Video cold and warm to see well (lambda (o2) sensor disconnected on the videos):
    Cold engine
    https://youtu.be/K_Qk1zNyWfY

    Warm engine
    https://youtu.be/k_oRLktis5E

    SPECS

    jp4 fully forged
    106 1.6 rally engine loom
    ECU 1300R Magnetti marelli iaw 8p.40 (already tried with the 1.6 Rallye 8p.16 it's the same phenomenon, pig rich when warm engine)
    New spark plugs, new coil, new filter gasoline everything is new
    FPR set to 3bar
    185cc injectors
    I do not have a stepper motor, just a tap to adjust the idle speed

    Lambda connected or disconnected it did the same thing, waters sensors switched on and off it's the same thing also.
    I cannot make a diagnostic check on this configuration.

    The only thing I'm not sure is wich water temp /temp sensor plug goes with what sensor... then wich sensor goes where ?if anyone can tell me where will these sensors go)

    Here is my 2 plugs for water probes (unless I am mistaken)






    unless it is normal that she turn like that on warm engine ?

    Thanks for your help !!
  2. Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.
    #2
    Have you tried another coil pack?
  3. L-plater Joined: Aug 2014 Posts: 36
    #3
    yes i tried, same results, if i accelerate smoothly its runs nice when warm btw but rich
  4. Saxperience Forum Bum Joined: Mar 2009 Stoke-on-trent Posts: 2640 Mk5 Golf GTTDI Mk2 VTR Project
    #4
    had a similar issue on the vtr and never solved it, changed coilpack, top ecu coolant sensor, lambda, map sensor, icv and tps, no change :/
  5. Infrequent Poster Joined: Jan 2016 Swansea Posts: 168 106 1.4 gti replica (ish) Fd rx7 1.3tt 106 1.1
    #5
    Have you tried another set of lambdas? A different ecu? Or maybe take off your exhaust and check your cat?
    Sounds like you're gonna have fun solving that!
  6. Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.
    #6
    Are you losing any water?
  7. L-plater Joined: Aug 2014 Posts: 36
    #7
    no water leak

    already tried another ecu (the magnetti marelli 8p.16 from 106 1600Rallye, same problem but worse (richer)
    already tried another lambda sensor, same problem.
    already tried another map sensor, car wont idle

    maybe there is a way to reset the ecu ?
  8. L-plater Joined: Aug 2014 Posts: 36
    #8
    The car dont have any exhaust yet, already tried with the standart exhaust, same problem.
  9. Saxperience Forum Bum Joined: Mar 2009 Stoke-on-trent Posts: 2640 Mk5 Golf GTTDI Mk2 VTR Project
    #9
    Quote:
    Originally Posted by stevo67 View Post
    Are you losing any water?
    would it be a head gasket issue if it was losing water?
  10. L-plater Joined: Aug 2014 Posts: 36
    #10
    no headgasket failure here, i just rebuild the engine, new seals everywhere, no oil and water leaks plus it was runing the same with my precedent 1.6 8v engine, same symptoms (richer at warm)
  11. L-plater Joined: Aug 2014 Posts: 36
    #11
    some news, i unplugged the 2 watertemp/temps sensors + o2 and the car seems runign the same on warm and cold engine, same idle speed.. intresting
  12. Infrequent Poster Joined: Jan 2016 Swansea Posts: 168 106 1.4 gti replica (ish) Fd rx7 1.3tt 106 1.1
    #12
    Usually you just leave the neg off the battery for 20 mins for reset, also I've heard you turn ignition (lights on, not crank) on and off 6 times after leaving neg off battery for 20 mins. Could try that!
    With the upgraded injectors, can your map sensor read it? Usually on the rx7s when the lads upgrade turbos, injectors, hp etc they have to switch from the stock map sensor to a 3 bar map sensor, I'm still getting my head around fuel/air mix and obviously they're going from 250bhp to 400+ so stock map sensor is useless!
    Is it possible this is happening with yours? (don't quote me on it, just throwing out some ideas)
    Maybe pm chipwizard or gmc they seem to have a real good knowledge of mapping!!!
  13. L-plater Joined: Aug 2014 Posts: 36
    #13
    for the mapping and everything else ill run an AEM fic + the aem fic map sensor itself or a 3bar map sensor, its not a problem.

    but before the fic, i want the car to run nice and without this kind of strange problemes that i had (seems fixed since i unplugged the 2 water temp sensors + o2 sensor)

    ill try to plug em one by one in order to see what sensor/plug is causing trouble


    thanks you for your ecu reset tip, ill try it