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VT is jerking when accelerating above 80kph

Discussion in 'VT - VX Holden Commodore (1997 - 2002)' started by DoubleX, Feb 12, 2019.

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  1. DoubleX

    DoubleX New Member

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    Hey guys,
    I need help with my VT V6. My car is jerking when I accelerate at 80-90kph. I can feel the jerking noticeably about 2-3 times then it goes away when I drive with a steady speed. It is also jerking when driving uphill at 70-80kph.
    I have checked the transmission fluid when it is warm, it is a bit above the maximum hot line on the dipstick. All spark plugs were replaced in 2016. The fuel pump was replaced in 2017. Also had the last regular service on 11/2018.

    Thank you in advance :)
     
  2. accentstencil

    accentstencil Well-Known Member

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    You haven't mentioned changing spark plug leads, so I suggest you try a new set. It may not be the problem but there is a good chance that it is.
     
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  3. immortality

    immortality Home of the smoky breakfast Bacon! Staff Member

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    Agree with the leads. Possibly a lean cruise miss. How many km on those plugs?
     
  4. mpower

    mpower Well-Known Member

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    another vote for leads, after i got my car back from getting extractors installed i developed a miss - it was leads thankfully i could just reseat them not shell out for a new set as they weren't that old. so yeah try a reseat first.
     
  5. DoubleX

    DoubleX New Member

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    They are about 23,000km now.
     
  6. _R_J_K_

    _R_J_K_ Well-Known Member

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    Time to change those plugs. Would also look at the fuel filter as it sounds like it happens when the engine needs the higher fuel flow and the filter could be partially clogged.
     
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  7. DoubleX

    DoubleX New Member

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    So I had a look at the leads, there were corrosion around the plugs and the coils. I used WD40 to clean them. Now my car is good and the acceleration is more responsive than before. Thanks heap guys!

    I've tried to replace the spark plugs but they didn't budge at all. Looks like the mechanic who put them last time didn't use an anti-seize agent. I'll leave them for my next service.
     
    Last edited: Feb 13, 2019
  8. _R_J_K_

    _R_J_K_ Well-Known Member

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    That's not a good sign. You should start using penetrating fluids now over a few days to a week to try and get them to free up, otherwise they're liable to snap off in the head and then you'll be in a world of hurt.

    If the heads on the spark plugs are also corroded, just use a wire brush till you get them silver again.
     
  9. DoubleX

    DoubleX New Member

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    I sprayed WD40 on those plugs and left them for a night but still no luck this morning.
     
  10. Juice3

    Juice3 Member

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    Mine had exact same problem I replaced all 6 leads and plugs and that fixed it
     
  11. JohnW

    JohnW New Member

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    As you know, the plugs are difficult to get at (I always have to take a few deep breaths before tackling the job). So my point is to give you the best chance of moving them, make sure you have the correct quality tools. Quality spark plug socket, the correct length extension, and quality ratchet spanner.

    With the correct tools so you can nice straight decent leverage I'd be confident you can move the suckers. Over 50 years in the trade and not had one beat me yet. Main problem is people do em up way too tight, just 'nip' tight is all that's necessary. They are spark plugs, not sump plugs.

    Good Luck.

    P.S. I agree with all the other posts. Replace the leads, plugs, fuel filter (buy the tool from Repco), and air filter. Only them start looking for what may be wrong if the problem persists.
     

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