Hi Rob
My 2003 Toyota Highlander V6 has 255,000 kilometres on it and generally speaking it runs great - it just keeps on going and going.
One problem - when it gets under 1/4 tank of gas it has a tendency (not every time) to chug or jerk when I maintain speed or decelerate, it's great as long as I am accelerating.
Can you help?
Thanks, Andrew
Two things Andrew: one obvious and one not so obvious.
The first possibility is that the vehicle is the low fuel. Gas caps have been known to have faulty pressure relief valves. The dealer should have a gas cap tester to check this out. As the fuel drops in the tank, the internal volume of fuel diminishes while the "air" volume increases. The fuel cap and the Evaporative Emissions (EVAP) system should be compensating for this. The simple fix is a new gas cap; the complicated fix is a diagnostic test of the EVAP system. There is a full blown diagnostic routine for this and one that should be a no-brainer for a Toyota dealership.
The second possibility is a little "out there." Some Toyota Powertrain Control Modules (PCMs), required a fuzzy logic upgrade. There is an upgraded, replacement PCM available for your vehicle but it will require extensive diagnosis to determine if this is the fault.
I would have your dealer start with the simple fix first.
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