Hi All, Wondering if anyone has experienced this, or has any suggestions on what I should look for to fix it. If I am driving at say 70kms an hour on a straight road (say engine revs are 1400 rpm), and I accelerate gently to about 1800 rpm, the car accelerates gently, and then the revs just fall to about 1500-1600 rpm (although the car continues to accelerate)! It's exactly as if it's changing from third to overdrive, but it's not - the gearbox is staying in 4th all the time. It's very unsettling to see the tacho just drop 250rpm when it shouldn't. Does anyone have a clue what might be the matter? Also, the VT is dual fuel... the behaviour is the same on petrol or LPG if this helps. Back to the gearbox, I think the gearbox could benefit from a service. I have a VS V6 auto as well, and the VS feels nice and tight - like if you pump the accelerator it kicks back and goes. However, the VT often won't kick back like the VS does given the same conditions. Also, the VS will positively change from first to second and it feels good, however if you give the VT a bit of stick, it will rev to about 4,000 rpm and then it feels like its almost free-revving (like slipping) and then it goes into second. It is smooth, but it just feels like it's not engaging quite right. Would this possibly have anything to do with the engine revs just dropping like they are? Could it be a totally independent problem? Does this sound expensive to fix? Any comments would be much appreciated! Cheers, John.
The rev drop sounds like your torque converter locking up. Thats normal. If the engine is under no load or very light load, the TC will lock up over 60km/h. Comparing the two cars and the way they change gears is not a good idea. The VT is heavier, has a different PCM and will behave differently than the VS. Give the VT's transmission a service and go from there.
