Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

Weird revs

Discussion in 'VR - VS Holden Commodore (1993 - 1997)' started by Benjamin Whiley, Mar 18, 2020.

  1. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    Hey, My vs commodore esteem s2 is running really weird I’ll be sitting on 80+ and the revs fluctuate from like 3000 to 2700 and I don’t know why. Do you have any ideas I have put new spark plugs newer coil pack new leads new fuel filter and new crank angle sensor
     
  2. Skylarking

    Skylarking Well-Known Member

    Messages:
    2,679
    Likes Received:
    1,310
    Trophy Points:
    113
    Joined:
    Feb 3, 2018
    Location:
    Downunder
    Members Ride:
    Commodore Motorsport
    Auto or manual?
    Auto I suspect... check the oil level or better still do a service (oil, filter, etc).
     
  3. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    Done a service 1500 km ago and yes auto
     
  4. Skylarking

    Skylarking Well-Known Member

    Messages:
    2,679
    Likes Received:
    1,310
    Trophy Points:
    113
    Joined:
    Feb 3, 2018
    Location:
    Downunder
    Members Ride:
    Commodore Motorsport
    1500kms can be anywhere from one week to a year in time, though for most it tends to be 3 weeks. But did this issue just start to occur or has it been their since the trans service and being progressively getting worse?

    And have you checked the trans fluid level in the last few days?

    Ps: I’m assuming some auto slip or flaring is occurring which is why your see fluctuating revs. May be worth clearly indicating how the revs are actually changing... for example driving at constant speed at 100kph with revs siting at 2700rpm then they jump to 3000rpm then they go back to 2700rpm. Yhis could be helpful as others may know the vehicles gearing and what revs should be at a given speed... slipping/flaring should see revs increase... cause some other engine issue like idle control valve issue could see different behaviour to auto flaring.
     
    Last edited: Mar 18, 2020
  5. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    My revs are going down and you can feel it lose power kind of, also if I am going 80+ the revs are also fluctuating between 2400-2000rpm

    the issue started just before I got it serviced about 4 weeks ago I thought I was misfiring but turns out it isnt
     
  6. losh1971

    losh1971 Well-Known Member

    Messages:
    7,791
    Likes Received:
    2,477
    Trophy Points:
    113
    Joined:
    Jan 17, 2010
    Location:
    North Tas
    Members Ride:
    VR Ute V6
    Test your TPS.
     
    Skylarking likes this.
  7. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    How do I test it
     
  8. Skylarking

    Skylarking Well-Known Member

    Messages:
    2,679
    Likes Received:
    1,310
    Trophy Points:
    113
    Joined:
    Feb 3, 2018
    Location:
    Downunder
    Members Ride:
    Commodore Motorsport
    TPS is basically a potentiometer where the resistance varies as the throttle is turned.

    The TPS connector has power (5V?), earth and signal wires. You measure the voltage on the signal wire while slowly opening the throttle. The voltage should slowly rise as you open the throttle. The voltage should not jump around or drop to zero and back up to a voltage as you turn.

    The best tool for doing such checks is an old style analog voltage meter.

    Others would be able to chime in at specific pinouts and voltage levels.

    More modern cars like VE or VF have OBD2 plug where you can plug on an ODB2 adapter and use your phone to read the TPS signal via a phone app. VS has ALDL wires within ODB plug which is a differet beasty.

    You can find the VR/VS service manual within this post and DTC list here
     
    Last edited: Mar 18, 2020
    losh1971 likes this.
  9. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    Just put a new tps in still no go, would dfi be next ??
     
  10. vs-lover

    vs-lover Well-Known Member

    Messages:
    1,785
    Likes Received:
    995
    Trophy Points:
    113
    Joined:
    Mar 9, 2013
    Location:
    Adelaide
    Members Ride:
    VS S2 Calais, VS S2 Exec Wagon, VS S2 Acclaim
    Personally I feel it's a trans issue as I had that with my Calais when I brought it back from Melbourne originally. I could be driving at 100k's and then suddenly the revs would skyrocket until I changed speed back down and reapply acceleration. I put this down to a trans that had done very little work (69,000k's) over 20 years and there was some kind of internal bypass of pressure.

    Just my thoughts.............got to ask how many K's has your vehicle done ?
     
  11. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    218000km if it is the trans what can I do to fix it or is it easier getting a new on, maybe manual swap?
     
  12. BlackVXGTS

    BlackVXGTS Well-Known Member

    Messages:
    3,580
    Likes Received:
    562
    Trophy Points:
    113
    Joined:
    Aug 14, 2004
    Location:
    Melbourne, SE
    Members Ride:
    GEN-F2 GTS A6, VS Clubsport 185 A4
    Sounds like you may have a torque converter clutch lockup problem. Refer to the article below from Kaps Automotive. I don't understand your comment about the "revs would skyrocket", when in other posts you are talking about a 200 rev variation.

    UNDERSTANDING THE LOCK UP CLUTCH
    When the impeller and the turbine are rotating at nearly the same speed, no torque multiplication is taking place. The torque converter is transmitting the input torque from the engine to the transmission at a ratio of almost 1:1. There is however, approximately 4-5% difference in rotational speed between the turbine and the impeller. The torque converter is not transmitting 100% of the power generated by the engine to the transmission, so there is energy loss.

    To prevent this, and to reduce fuel consumption, the lock up clutch mechanically connects the impeller and turbine when the vehicle is around 37mph or higher. When the lock up clutch is engaged, 100% of the power is transferred through the torque converter.

    The lock up clutch is installed on the turbine hub, in front of the turbine. The dampening spring absorbs the torsional force upon clutch engagement to prevent shock transfer. The friction material bonded to the lock up piston is the same as that used on the multiplate clutch discs in the transmission.
     
  13. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    I never said “the revs skyrocket”
     
  14. vs-lover

    vs-lover Well-Known Member

    Messages:
    1,785
    Likes Received:
    995
    Trophy Points:
    113
    Joined:
    Mar 9, 2013
    Location:
    Adelaide
    Members Ride:
    VS S2 Calais, VS S2 Exec Wagon, VS S2 Acclaim
    No Ben that was me and BlackVXGTS has accidentally gotten that mixed up with you as it was the case for me. Mine was basically pressure loss inside the trans at times due to lack of usage I'd say and seals going a bit hard over time. In your case I now feel this would not be the case as your trans has done quite a bit more work over time and everything inside would be far more supple.

    I think Blacky is on to something there with his post.
     
  15. _R_J_K_

    _R_J_K_ Well-Known Member

    Messages:
    4,678
    Likes Received:
    485
    Trophy Points:
    83
    Joined:
    Dec 20, 2008
    Members Ride:
    Zenki S14
    Don't discount vacuum leaks, have a look around the PCV pipe and in the folds of the intake pipe, also the pipe to the brake booster. Could even be a leak that only opens up under heaps of vacuum. Does anything happen lower than that?
     
  16. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    under 80km an hour the car runs like a dream, has higher revs after cold start but yeah that’s pretty normal isn’t it
     
  17. Benjamin Whiley

    Benjamin Whiley Member

    Messages:
    35
    Likes Received:
    3
    Trophy Points:
    8
    Joined:
    Jan 30, 2020
    Location:
    Biloela
    Members Ride:
    VS Esteem S2
    There was also a little bit of what looked like oil in the intake pipe
     

Share This Page