Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

vn v8 motor problems

Discussion in 'VN - VP Holden Commodore (1988 - 1993)' started by overclocked23, Apr 14, 2009.

  1. overclocked23

    overclocked23 Member

    Messages:
    31
    Likes Received:
    0
    Trophy Points:
    6
    Joined:
    Mar 23, 2009
    Members Ride:
    Vp V8
    i have a vn v8 and im having trouble with the motor when i get in to the higher rpm the motor breaks down like missing as well as it feels like the engine is laggy as well . i replaced the fuel filter and when i did the element inside was loose and was not filtering at all and was clogged to the **** house as we opened it up cause never seen one were the element was loose , i was thinking of replacing the internal and external pumps and the regulator and injectors, as well as that the car starts stright away when cold but once warmed up it takes a bit more cranking over so that gets me thinkin its the pumps any help would be nice thanks
     
  2. VrWagz1

    VrWagz1 The Wagon on Wheels..

    Messages:
    2,438
    Likes Received:
    27
    Trophy Points:
    48
    Joined:
    May 5, 2008
    Location:
    wollongong
    Members Ride:
    VE SSV MY09 Auto Wagon
    They can be a bit hard to start when hot. Try turning the key once so the pump will prime for just a few seconds and then off and then back on let it prime again and then crank. Works with mine.

    If its starts spluttering up high it can be a dodgy dizzy cap and even your leads. How long since you done the spark plugs. Generally but not always if it lacks fuel it will just run boggy as opposed to miss firing.
     
  3. greenfoam

    greenfoam New Member

    Messages:
    7,900
    Likes Received:
    119
    Trophy Points:
    0
    Joined:
    Jan 13, 2005
    Members Ride:
    VP Executive R-spec
    Coil maybe
     
  4. PaRaDoX

    PaRaDoX Because Racecouch...

    Messages:
    3,286
    Likes Received:
    31
    Trophy Points:
    48
    Joined:
    Apr 16, 2005
    Location:
    Melbourne, Victoria
    Members Ride:
    none
  5. overclocked23

    overclocked23 Member

    Messages:
    31
    Likes Received:
    0
    Trophy Points:
    6
    Joined:
    Mar 23, 2009
    Members Ride:
    Vp V8
    well changed the sparkplugs yesterday i will try the leads and cap and c what happens thanks
     
  6. Vt-Brrrlina

    Vt-Brrrlina vp bt1 gts replica

    Messages:
    521
    Likes Received:
    4
    Trophy Points:
    0
    Joined:
    May 2, 2006
    Location:
    Perth, Western Aust
    Members Ride:
    vp bt1 5.0ltr full GTS kit
    if ya doin the cap do the rotor same time - mine was cracked causing backfiring and laggy car
     
  7. spirto

    spirto Member

    Messages:
    213
    Likes Received:
    3
    Trophy Points:
    18
    Joined:
    Aug 2, 2006
    Location:
    Adelaide
    Members Ride:
    VQ Caprice II
    Hey guys,
    If it is hard to start when it's hot, it is usually caused by the one or more injectors dribbling into the inlet manifold when it is parked. It takes two or three cranks as it has to spit out the extra fuel. When you turn the key again it will only add more fuel. A quick test is to remove the fuel pump fuse and start it when hot, if it starts quickly then stall then it will confirm that the fuel injectors are dribbling.

    In regards to your engine performance up high, sounds like a coil or leads, spark plugs tend to misfire only at low rpm almost idle. I would also check the fuel regulator located at the rear of the driver side bank, there is a little vacuum hose that can split causing the fuel to not flow.

    Another check and quite common is inside the distrubuter there are mechanical wieghts to allow the dizzy to advance as needed, these can become stuck or rusted. Ebay sells new dissys all the time.

    Hope this helps.
     
  8. Reaper

    Reaper Tells it like it is.

    Messages:
    6,340
    Likes Received:
    1,607
    Trophy Points:
    113
    Joined:
    Aug 15, 2004
    Location:
    SE Suburbs, Melbourne
    Members Ride:
    VZ LX8 Adventra, VP SS
    coil / leads / plugs.
    I'd put money on coil myself. Fix all vac lines. Dizzy advance is done in the ECU. If you put a procomp dizzy in your car you will be banished from jc hence forth.

    Reaper
     

Share This Page